Answer: 36 shingles can be placed on the north part of the house.
Step-by-step explanation:
Given: Length of each shingle = [tex]1\dfrac23[/tex] feet = [tex]\dfrac53[/tex] feet.
The north part of the house has a roof line that is 60 feet across.
Then, the number of shingles can be placed on the north part of the house = (Length of roof line in north part) ÷ (Length of each shingle)
[tex]=60\div \dfrac{5}{3}\\\\=60\times\dfrac{3}{5}\\\\=12\times3=36[/tex]
Hence, 36 shingles can be placed on the north part of the house.
Kevin made a business trip of 312.5 miles. He averages 60 mph for the first part of the trip and 55 mph for the second part. If the trip took a 5.5 hours how long did he travel at each rate
Answer:
Kevin travels for 2 hours at 60 mph and 3.5 hours at 55 mph
Step-by-step explanation:
Let's say that Kevin spends x hours going 60 mph and y hours going 55 mph. We can say that the sum of the two parts is 5.5, so x+y = 5.5 . Next, he goes 60 miles per hour for the first part of the trip, so for each hour he goes 60 mph, he travels 60 miles. We can then denote 60 * x as the distance traveled during the first part of his trip as he goes 60 mph for x hours. Similarly, 55 * y denotes the distance Kevin travels during the second part of his trip. His total distance is thus 60 * x + 55 * y = 312.5 miles
We have
x + y = 5.5
60 * x + 55 * y = 312.5
One way we can solve this is to solve for y in the first equation and plug that into the second. Subtracting x from both sides in the first equation, we get
y = 5.5 - x
Plugging that into the second equation, we get
60 * x + 55 * (5.5-x) = 312.5
60 * x + 55 * 5.5 - 55x = 312.5
5x +302.5 = 312.5
subtract 302.5 from both sides to isolate the x and its coefficient
5x = 10
divide both sides by 5 to solve for x
x = 2
y = 5.5 - x = 5.5 - 2 = 3.5
Therefore, Kevin travels for 2 hours at 60 mph and 3.5 hours at 55 mph
Hi Mathies, Help with this vectors excercise pls. Givan that OA (segment) = 13x+7y , OB = 5x+12y and CO = -15+12y write down each of the following vectors in its simplest form a) BA = 8x+ 5y (l got it, i ve done it) b) AC= ?? i cant find vector AC thanks in advance
Answer:
AC = 2x-19yStep-by-step explanation:
Given vector the following vector equations OA = 13x+7y , OB = 5x+12y and CO = -15x+12y, the following expression is true about vector OA, OB and OC;
OA+OB = CO (CO is the resultant since its is moving in the opposite direction compare to OA and OB)
Also BO+OA = BA and AO+OC = AC
If OB = 5x+12y, then BO = -(5x+12y)
BO = -5x-12y (BO = -OB)
Since BO+OA = BA
BA = -5x-12y + 13x+7y
BA = -5x+13x-12y+7y
BA = 8x-5y
Similarly AO+OC = AC
Since AO = -OA and OC = -CO
-OA-CO = AC
AC = -(13x+7y)-(-15x+12y)
AC = -13x-7y+15x-12y
AC = -13x+15x-7y-12y
AC = 2x-19y
Find the doubling time of an investment earning 8% interest if interest is compounded continuously. The doubling time of an investment earning 8% interest if interest is compounded continuously is ____ years.
Answer:
8.66 years
Step-by-step explanation:
Given that:
Interest rate = 8%
Using the exponential growth function:
A = Ao * e^(rt)
Where A = final amount
Ao = Initial amount
r = growth rate
t = time
Here we are to calculate the time it takes an investment earning 8% interest to double;
rate (r) = 8% = 0.08
2A = A * e^(rt)
Divide both sides by A
2 = e^(rt)
2 = e^(0.08 * t)
2 = e^(0.08t)
In(2) = 0.08t
0.6931471 = 0.08t
Divide both sides by 0.08
0.6931471 / 0.08 = 0.08t / 0.08
8.6643397 = t
t = 8.66 years
Answer:
symbolically, the answer would be t= ln(2)/(.08)
Step-by-step explanation:
start by writing out your variables:
rate= .08
*dont forget the investment doubles too, thats where 2P is in the bottom equation
equation should look like:
[tex]2P=Pe^{.08t}[/tex]
then you solve, so divide P on the right and left:
[tex]\frac{2p}{p} = \frac{Pe^{.08t}}{p}[/tex]
now it looks like: [tex]2=e^{.08t}[/tex]
you can take the natural log (ln) of 2 to get the exponent by itself .08t
ln(2)=.08t
then divide .08 to get t by itself
[tex]\frac{ln(2)}{.08} =\frac{.08t}{.08}[/tex]
so symbolically, your equation should be:
[tex]t=\frac{ln(2)}{.08}[/tex]
to get t as your answer you can plug this equation into your calculator to get:
t=8.66 years so approximently 8 years
Given that log 2 = 0.3010 and log 7 = 0.8451, find the following (a) log 49 (b) log 560
Answer:
ok babababr
Step-by-step explanation:
skwjshehhehdhhshwhhdhwhbeujsbsgehbedheb
Answer:
Log 49= 1.6902
Log 560= 1.7481
Step-by-step explanation:
log49= log7×7
From the rules of logarithms, we have that
log a×b= log a + log b
So log49= log7×7= log7 + log7
= 0.8451 + 0.8451 = 1.6902
Log 560 = log7×8 = log7 + log8
log8= log2^3 = 3log2
log8= 3×0.3010 =0.930
log 560= 0.8451 + 0.930 = 1.7481
Urgent please I neeed some help !!!!!!!!!!!!!!!!!!!!!! URGENT 20 point bonus
Answer:
113.1
Step-by-step explanation:
use the formula to solve for volume
A study of 200 computer service firms revealed these incomes after taxes: Income After Taxes Number of Firms Under $1 million 102 $1 million up to $20 million 61 $20 million or more 37 What is the probability that a particular firm selected has $1 million or more in income after taxes
Answer:
The probability that a particular firm selected has $1 million or more in income after taxes is 49%.
Step-by-step explanation:
We are given a study of 200 computer service firms revealed these incomes after taxes below;
Income After Taxes Number of Firms
Under $1 million 102
$1 million up to $20 million 61
$20 million or more 37
Total 200
Now, the probability that a particular firm selected has $1 million or more in income after taxes is given by;
Total number of firms = 102 + 61 + 37 = 200
Number of firms having $1 million or more in income after taxes = 61 + 37 = 98 {here under $1 million data is not include}
So, the required probability = [tex]\frac{\text{Firms with \$1 million or more in income after taxes}}{\text{Total number of firms}}[/tex]
= [tex]\frac{98}{200}[/tex]
= 0.49 or 49%
The probability that a particular firm selected has $1 million or more in income after taxes is 0.49 or 49%.
What is probability?Probability means possibility. It deals with the occurrence of a random event. The value of probability can only be from 0 to 1. Its basic meaning is something is likely to happen. It is the ratio of the favorable event to the total number of events.
A study of 200 computer service firms revealed these incomes after taxes:
Income After Taxes Number of Firms Under
$1 million 102
$1 million up to $20 million 61
$20 million or more 37.
Then the total event will be
Total event = 102 + 37 +61 = 200
The probability that a particular firm selected has $1 million or more in income after taxes will be
Favorable event = 37 + 61 = 98
Then the probability will be
[tex]\rm P = \dfrac{98}{200} \\\\P = 0.49 \ or \ 49 \%[/tex]
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How many fluid ounces are there in 4pints?
Answer: 64 fluid ounces
Step-by-step explanation:
1 pint=16 fl oz
16*4=64
how many years will it take for a sum of money to double at 10% compounded annually
Answer:
t=7.27 years
Step-by-step explanation:
Let the money be p and t will be the number of years that will be needed for the money to get double.
ATQ, 2p=p*(1+0.1)^t
2=(1.1)^t
log(2)/log(1.1)=t, t=7.27
Emile is a long-distance trucker. In one week he drives miles from his home in Fort Lauderdale, FL, to Benson, NC. He then drives miles to Barstow, CA, and continues driving miles to Bakersfield, CA. From there, Emile drives miles to Seattle, WA. Estimate the total distance Emile travels by first rounding each distance to the nearest hundred. Do not put units in your answer.
Answer:
Estimated total distance is 1,900 miles.
Step-by-step explanation:
We begin by adding each distance traveled by Emile:
1. Fort Lauderdale, FL, to Benson, NC = 748 miles
2. Barstow, CA, to Bakersfield, CA = 130 miles
3. Bakersfield, CA. to Seattle, WA = 1030 miles
Total miles = 1,908.
Therefore, in one week Emile's total distance to the nearest hundred is 1,900.
Note: the distances where gotten via Google Map.
2. A dolphin leaps 5 feet in the air at the same time an orca whale dives 12 feet below the water. How far apart are the whale and the dolphin?
is perpendicular to . How many 90° angles are formed by the intersection?
Answer:
if a is perpendicular to b then four 90 degree angles are formed
Step-by-step explanation:
if a line is perpendicular to another that means that it forms a 90 degree angle on all of the angles
Answer:
Four
That is the right answer for Edmentum and Plato users
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Solve the following equation for x to find the total number of sale items stocked on the shelves of a toy store for a certain week: x = 0.7x + 24 How many total items were stocked for that week? 14 56 80 10
Answer:
80
Step-by-step explanation:
The total of 80 items were stocked for that week.
What is a system of equations?
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
Solve equation for x to find the total number of sale items stocked on the shelves of a toy store for a certain week:
x = 0.7x + 24
We need to find How many total items were stocked for that week
Solving;
x = 0.7x + 24
x - 0.7x = 24
0.3x = 24
x = 80
Therefore, the total of 80 items were stocked for that week.
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Find the work done by the force field F(x,y,z)=6xi+6yj+6k on a particle that moves along the helix r(t)=3 cos(t)i+3sin(t)j+2 tk,0≤t≤2π.
Answer:
the work done by the force field = 24 π
Step-by-step explanation:
From the information given:
r(t) = 3 cos (t)i + 3 sin (t) j + 2 tk
= xi + yj + zk
∴
x = 3 cos (t)
y = 3 sin (t)
z = 2t
dr = (-3 sin (t)i + 3 cos (t) j + 2 k ) dt
Also F(x,y,z) = 6xi + 6yj + 6k
∴ F(t) = 18 cos (t) i + 18 sin (t) j +6 k
Workdone = 0 to 2π ∫ F(t) dr
[tex]\mathbf{= \int \limits ^{2 \pi} _{0} (18 cos (t) i + 18 sin (t) j +6k)(-3 sin (t)i+3cos (t) j +2k)\ dt}[/tex]
[tex]\mathbf{= \int \limits ^{2 \pi} _{0} (-54 \ cos (t).sin(t) + 54 \ sin (t).cos (t) + 12 ) \ dt}[/tex]
[tex]\mathbf{= \int \limits ^{2 \pi} _{0} 12 \ dt}[/tex]
[tex]\mathbf{= 12 \times 2 \pi}[/tex]
= 24 π
4. Find the area of the polygon.
Answer:
20
Step-by-step explanation:
Please! David has several chains of length 5 and of length 7. By joining chains one after the other, David can create different lengths. Which of these lengths is impossible to make? A)10 B)12 C)13 D)14 E)15
Answer:
13
Step-by-step explanation:
A)5+5=10
B)5+7=12
C) impossible
D)7+7=14
E)5+5+5=15
Isreal spends the most time on social media with a total of 11.1.peru has a total of 8.3 how much more time does israel spend on social media
Answer:
2.8
Step-by-step explanation:
11.1-8.3=2.8
HOPE I HELPED
PLS MARK BRAINLIEST
DESPERATELY TRYING TO LEVEL UP
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JUST A RANDOM GIRL WANTING TO HELP PEOPLE!
PEACE!
An urn contains two blue balls (denoted B1 and B2) and three white balls (denoted W1, W2, and W3). One ball is drawn, its color is recorded, and it is replaced in the urn. Then another ball is drawn and its color is recorded.
a. Let B1 W2 denote the outcome that the first ball drawn is B1 and the second ball drawn is W2. Because the first ball is replaced before the second ball is drawn, the outcomes of the experiment are equally likely. List all 25 possible outcomes of the experiment.
b. Consider the event that the first ball that is drawn is blue. List all outcomes in the event. What is the probability of the event?
c. Consider the event that only white balls are drawn. List all outcomes in the event. What is the probability of the event?
Answer:
(a) Shown below.
(b) The probability that the first ball drawn is blue is 0.40.
(c) The probability that only white balls are drawn is 0.36.
Step-by-step explanation:
The balls in the urn are as follows:
Blue balls: B₁ and B₂
White balls: W₁, W₂ and W₃
It is provided that two balls are drawn from the urn, with replacement, and their color is recorded.
(a)
The possible outcomes of selecting two balls are as follows:
B₁B₁ B₂B₁ W₁B₁ W₂B₁ W₃B₁
B₁B₂ B₂B₂ W₁B₂ W₂B₂ W₃B₂
B₁W₁ B₂W₁ W₁W₁ W₂W₁ W₃W₁
B₁W₂ B₂W₂ W₁W₂ W₂W₂ W₃W₂
B₁W₃ B₂W₃ W₁W₃ W₂W₃ W₃W₃
There are a total of N = 25 possible outcomes.
(b)
The sample space for selecting a blue ball first is:
S = {B₁B₁, B₁B₂, B₁W₁, B₁W₂, B₁W₃, B₂B₁, B₂B₂, B₂W₁, B₂W₂, B₂W₃}
n (S) = 10
Compute the probability that the first ball drawn is blue as follows:
[tex]P(\text{First ball is Blue})=\frac{n(S)}{N}=\frac{10}{25}=0.40[/tex]
Thus, the probability that the first ball drawn is blue is 0.40.
(c)
The sample space for selecting only white balls is:
X = {W₁W₁, W₂W₁, W₃W₁, W₁W₂, W₂W₂, W₃W₂, W₁W₃, W₂W₃, W₃W₃}
n (X) = 9
Compute the probability that only white balls are drawn as follows:
[tex]P(\text{Only White balls})=\frac{n(X)}{N}=\frac{9}{25}=0.36[/tex]
Thus, the probability that only white balls are drawn is 0.36.
Nala can spend no more than $150 per month on gasoline. She has already purchased $60 in gas this month. Which inequality can be used to find the maximum number of fill-ups she can purchase during the rest of the month, assuming each fill-up costs $30? 30n + 60 > 150 30n + 60 150
Answer:
150<60+30n
Step-by-step explanation:
150 is the maximum amount that she can spend on gas. (which is the total)
she already spend $60
each fill up (n) costs 30
Answer:
the answer is B)
Step-by-step explanation:
Makayla wants to make 200 mL of a 18% saline solution but only has access to 8% and 24% saline mixtures.
Which of the following system of equations correctly describes this situation if x represents the amount of the 8% solution used, and y represents the amount of the 24% solution used?
Answer:
x + y = 200
0.08x + 0.24y = 0.18(200)
Step-by-step explanation:
x + y = 200
0.08x + 0.24y = 0.18(200)
The equations which describes the amount of 8% solution used and the amount of 24% solution used are: x+ y=200 and x+3y=450.
What is equation?An equation is a relationship between two or more variables. They are mostly present in equal to form and are equated to find the value of variables present in them.
How to form equation?let the amount of 8% solution used be x and the amount of 24% solution used be y.
According to question the amount of total solution will be 200ml, So, the equation will be:
x +y=200
Now we have been said that the solution will be 18% saline and 8% saline mixture and 24% saline mixtures are used, So the next equation will be:
0.08x+ 0.24y=0.18*200
8x/100+24/100=18/100*200
8x+24y=3600
8(x+3y)=3600
x+3y=450
Hence the equations which shows the amount of solutions will be x+y=200 and x+3y=450.
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Consider the differential equation:
2y'' + ty' − 2y = 14, y(0) = y'(0) = 0.
In some instances, the Laplace transform can be used to solve linear differential equations with variable monomial coefficients.
If F(s) = ℒ{f(t)} and n = 1, 2, 3, . . . ,then
ℒ{tnf(t)} = (-1)^n d^n/ds^n F(s)
to reduce the given differential equation to a linear first-order DE in the transformed function Y(s) = ℒ{y(t)}.
Requried:
a. Sovle the first order DE for Y(s).
b. Find find y(t)= ℒ^-1 {Y(s)}
(a) Take the Laplace transform of both sides:
[tex]2y''(t)+ty'(t)-2y(t)=14[/tex]
[tex]\implies 2(s^2Y(s)-sy(0)-y'(0))-(Y(s)+sY'(s))-2Y(s)=\dfrac{14}s[/tex]
where the transform of [tex]ty'(t)[/tex] comes from
[tex]L[ty'(t)]=-(L[y'(t)])'=-(sY(s)-y(0))'=-Y(s)-sY'(s)[/tex]
This yields the linear ODE,
[tex]-sY'(s)+(2s^2-3)Y(s)=\dfrac{14}s[/tex]
Divides both sides by [tex]-s[/tex]:
[tex]Y'(s)+\dfrac{3-2s^2}sY(s)=-\dfrac{14}{s^2}[/tex]
Find the integrating factor:
[tex]\displaystyle\int\frac{3-2s^2}s\,\mathrm ds=3\ln|s|-s^2+C[/tex]
Multiply both sides of the ODE by [tex]e^{3\ln|s|-s^2}=s^3e^{-s^2}[/tex]:
[tex]s^3e^{-s^2}Y'(s)+(3s^2-2s^4)e^{-s^2}Y(s)=-14se^{-s^2}[/tex]
The left side condenses into the derivative of a product:
[tex]\left(s^3e^{-s^2}Y(s)\right)'=-14se^{-s^2}[/tex]
Integrate both sides and solve for [tex]Y(s)[/tex]:
[tex]s^3e^{-s^2}Y(s)=7e^{-s^2}+C[/tex]
[tex]Y(s)=\dfrac{7+Ce^{s^2}}{s^3}[/tex]
(b) Taking the inverse transform of both sides gives
[tex]y(t)=\dfrac{7t^2}2+C\,L^{-1}\left[\dfrac{e^{s^2}}{s^3}\right][/tex]
I don't know whether the remaining inverse transform can be resolved, but using the principle of superposition, we know that [tex]\frac{7t^2}2[/tex] is one solution to the original ODE.
[tex]y(t)=\dfrac{7t^2}2\implies y'(t)=7t\implies y''(t)=7[/tex]
Substitute these into the ODE to see everything checks out:
[tex]2\cdot7+t\cdot7t-2\cdot\dfrac{7t^2}2=14[/tex]
If a person invested half of her money at 9% and half at 7% and received $160 interest, find the total amount of money invested.
Answer:
$2000
Step-by-step explanation:
let x be the money she invested
lets assume this was for 1 year
0.09(x/2) + 0.07(x/2) = 160
multiply each side by 2 to cancel the denominators:
0.09x + 0.07x = 320
0.16x = 320
x = 2000
Answer: $2000
Let the amount of money she invested be x
Lets assume the time of investment as 1 year
ATQ
0.09(x/2) + 0.07(x/2) = 160
0.09x + 0.07x = 320
0.16x = 320
x = 2000
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find the slope of the line (-3,-2) (1,6)
Answer:
slope = 2
Step-by-step explanation:
Calculate the slope m using the slope formula
m = [tex]\frac{y_{2}-y_{1} }{x_{2}-x_{1} }[/tex]
with (x₁, y₁ ) = (- 3, - 2) and (x₂, y₂ ) = (1, 6)
m = [tex]\frac{6-(-2)}{1-(-3)}[/tex] = [tex]\frac{6+2}{1+3}[/tex] = [tex]\frac{8}{4}[/tex] = 2
write the equation of a horizontal ellipse with a major axis of 18, and minor axis of 10, and a center at (-4, 5).
See the attached picture
[tex]\bold{\text{Answer:}\quad \dfrac{(x+4)^2}{81}+\dfrac{(y-5)^2}{25}=1}[/tex]
Step-by-step explanation:
A "horizontal" ellipse means that the x-radius is bigger than the y-radius. Thus, x is the major axis and y is the minor axis.
The equation of an ellipse is: [tex]\dfrac{(x-h)^2}{a^2}+\dfrac{(y-k)^2}{b^2}=1[/tex] where
(h, k) is the center of the ellipsea is the radius on the x-axisb is the radius on the y-axisIt is given that the center is at (-4, 5) --> h = -4, k = 5
It is given that the major axis has a length of 18 --> x-radius = 9
It is given that the minor axis has a length of 10 --> y-radius = 5
Input those values into the equation of an ellipse to get:
[tex]\dfrac{(x-(-4))^2}{9^2}+\dfrac{(y-5)^2}{5^2}=1[/tex]
Simplify to get:
[tex]\dfrac{(x+4)^2}{81}+\dfrac{(y-5)^2}{25}=1[/tex]
Point A is at (2, -8) and point C is at (-4, 7).
Find the coordinates of point B on AC such that the ratio of AB to BC is 2:1.
Answer:
(-2, 2)
Step-by-step explanation:
Given:
Point A is at (2, -8) and point C is at (-4, 7)Difference of coordinates:
Δx = 2 - (-4) = 6Δy = - 8 - 7 = - 15The ratio of AB to AC is 2:1. So:
AB = 2*AC/3 and BC = AC/3Then coordinates of point B should be 2/3 from the point A:
x = 2- 6*2/3 = 2 - 4 = -2y = - 8 - (-15)*2/3 = -8 + 10 = 2So point B has coordinates of (-2, 2)
help pls, i have to get this correct
Answer:
Table C
Step-by-step explanation:
r = j+3
In table A
j = 12 so r = 12+3 = 15 not true so it does not fit the equation
In table B
j = 3 so r = 3+3 = 6 not true so it does not fit the equation
In table C
j = 6 so r = 9+3 = 9 this could be the table
In table D
j = 27 so r = 27+3 = 30 not true so it does not fit the equation
I NEED ALGEBRA HELP! Can you solve a system of equations using the substitution by solving one equation for x or y and then using the substitution method? x + 6y = 6 and 7x - 5y = -5
Answer:
let x be y
NOW,
X+6Y=6
Y+6Y=6
7Y=6
Y=0.87
The price of a technology stock was $ 9.56 yesterday. Today, the price rose to $ 9.69 . Find the percentage increase. Round your answer to the nearest tenth of a percent.
Answer and Step-by-Step explanation:
% increase = 100 x [(new price) - (original price)] / (original price)] = 100 (9.67 - 9.56) / 9.56
% increase ≅ 1.2% (to the nearest tenth)
1. Quadratics: The path of the longest shot put by the Women’s track team at Sun Devil U is modeledby h(x) = -0.015x2 + 1.08x + 5.8, where x represents the horizontal distance from the start and h(x) isthe height of the shot put above the ground. (Both x and h(x) are measured in feet.)a. [3 pts] Determine h(24). Round your answer to 2 decimal places.
Answer:
23.08 feetStep-by-step explanation:
If the path of the longest shot put by the Women’s track team at Sun Devil U is modeled by h(x) = -0.015x² + 1.08x + 5.8 where x represents the horizontal distance from the start and h(x) is the height of the shot put above the ground, to determine h(24), we will have to substitute x = 24 into the modeled equation as shown;
[tex]h(x) = -0.015x^2 + 1.08x + 5.8\\\\if \ x = 24;\\\\h(24) = -0.015(24)^2 + 1.08(24) + 5.8\\\\h(24) = -0.015(576)+25.92+5.8\\\\h(24) = -8.64+31.72\\\\h(24) = 23.08\\[/tex]
Hence the value of the height at the horizontal distance of 24 feet is 23.08 feet to 2 decimal place.
Patios can be made by mixing cubic meters of ash, stone, and wood chips in the ratio 5:7:3. How much stone is needed to make 45 cubic meters of patio?
Answer:
21 m^3
Step-by-step explanation:
5 + 7 + 3 = 15
The ratio of stone to the total is
7:15
If the total needed is 45 m^3, then we multiply both parts of the ratio by 3.
7 * 3 : 15 * 3
21:45
Answer: 21 m^3
help me besties pls and have a good Bestie
Answer:
6
Step-by-step explanation:
Area = length x width
Input the numbers:
Area = 78
length = 13
78 = 13 x width
width = 78 / 13
width = 6
If my answer is incorrect, pls correct me!
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-Chetan K
Answer:
Width=6m
Step-by-step explanation:
Area=78m^2
Length=13m
width=?(let width be x)
[AREA OF RECTANGLE=length× width]
78=13×x
78=13x
×=6