The temperature at 9:00 a.m. was 4°C. At 7:00 p.m., the temperature
was -12°C. What was the change in temperature (in degrees Celsius)?
�� 8-degree decrease
�� 16-degree decrease
�� 8-degree increase
�� 16-degree increase

1:-

[tex]\\ \sf \longmapsto 4+8r-6r=6+2r[/tex]

[tex]\\ \sf \longmapsto 4+2r=6+2r[/tex]

[tex]\\ \sf \longmapsto 2r-2r=6-4[/tex]

[tex]\\ \sf \longmapsto 0=2[/tex]

[tex]\\ \sf \longmapsto r=\infty[/tex]

2:-

[tex]\\ \sf \longmapsto 1-3x=-6+7-2x-x[/tex]

[tex]\\ \sf \longmapsto 1-3x=1-3x[/tex]

[tex]\\ \sf \longmapsto 0=0[/tex]

[tex]\\ \sf \longmapsto x=\infty[/tex]

Answer:

answer is 90°

Step-by-step explanation:

it's simple , these both angles are complementary so sum of both is 90°

I hope it helped:)

Answer:

see below

Step-by-step explanation:

58+32 = 90

The angles add to 90 degrees, so the angles are complementary

Answer:

31.5cm²

Step-by-step explanation:

area of a triangle =1/2 b h

b= 7cm

h=9cm

1/2×7×9

= 1/2×63

= 31.5cm²

hypotenuse is unknown so,

c²=a²+b²

c²= 7² + 9²

= 49 + 81

c²= 130

c= 11.4cm

perimeter= 7 +9+11.4

=27.4cm

pls note that no unit was stated

Answer:

[tex] \frac{ \cos(80) }{ \sin(10) } + \frac{ \sin(20) }{ \cos(70) } = 2 \\ \frac{ \cos(90 - 10) }{ \sin(10) } + \frac{ \sin(20) }{ \cos(9 0 - 20) } = 2 \\ \frac{ \sin(10) }{ \sin(10) } + \frac{ \sin(20) }{ \sin(20) } = 2 \\ 1 + 1 = 2 \\ 2 = 2 \\ \\ \frac{ \cot(40) }{ \tan(50) } + \frac{ \cos(65) }{ \sin(115) } = 2 \\ \frac{ \cot(90 - 50) }{ \tan(50) } + \frac{ \cos(65) }{ \sin(90 + 65) } = 2 \\ \frac{ \tan(50) }{ \tan(50) } + \frac{ \cos(65) }{ \cos(65) } = 2 \\ 1 + 1 \\ = 2[/tex]

Answer:

Answer is x=1 inthe sentences

Answer:

96

Step-by-step explanation:

[tex]\frac{24*64}{4*4}=96\\[/tex]

or

[tex]\frac{24}{4}=6, \frac{64}{4}=16\\6*16=96[/tex]

The minimum number of tiles that will be needed to completely cover the countertop to its edges is 96.

The space occupied by any two-dimensional figure in a plane is called the area. The space occupied by the rectangle in a two-dimensional plane is called the area of the rectangle.

The number of tiles will be calculated by calculating the area of the rectangular kitchen and the area of a tile then dividing the whole area by the area of a tile.

Area of kitchen,

A(k) = 64 x 24 = 1536 Square inches

Area of a tile,

A(T) = 4 x 4 = 16 square inches.

Divide the area of the kitchen by the area of a tile.

N = 1536 / 16 = 96 tiles

Therefore, the minimum number of tiles that will be needed to completely cover the countertop to its edges is 96.

To know more about an area follow

https://brainly.com/question/25292087

#SPJ2

Answer:

c

Step-by-step explanation:

Answer:

=2^5+5^5

=32+3125

=3157

Answer:

Kindly check explanation

Step-by-step explanation:

Given that :

Correlation Coefficient (r) = 0.989

alph=0.05

Number of observations (n) = 8

determine if there is a linear correlation between chest size and weight.

Yes, there exists a linear relationship between chest size and weight as the value of the correlation Coefficient exceeds the critical value.

What proportion of the variation in weight can be explained by the linear relationship between weight and chest size?

To determine the the proportion of variation in weight that can be explained by the linear regression line between weight and chest size, we need to obtain the Coefficient of determination(r^2) of the model.

r^2 = square of the correlation Coefficient

r^2 = 0.989^2 = 0.978121

Hence, about 0.978 (97.8%) of the variation in weight can be explained by the linear relationship between weight and chest size.

Let s(t) be the amount of salt in the tank at time t. Then s(0) = 50 lb.

Salt flows into the tank at a rate of

(2 gal/min) (6 lb/gal) = 12 lb/min

and flows out at a rate of

(2 gal/min) (s(t)/300 lb/gal) = s(t)/150 lb/min

so that the net rate at which salt is exchanged through the tank is

ds(t)/dt = 12 - s(t)/150 … (lb/min)

Solve for s(t). The DE is separable, so we have

ds/dt = 12 - s/150

150 ds/dt = 1800 - s

150/(1800 - s) ds = dt

Integrate both sides to get

-150 ln|1800 - s| = t + C

Solve for s :

ln|1800 - s| = -t/150 + C

1800 - s = exp(-t/150 + C )

1800 - s = C exp(-t/150)

s = 1800 - C exp(-t/150)

Now given that s(0) = 50, we solve for C :

50 = 1800 - C exp(-0/150)

50 = 1800 - C

C = 1750

Then the amount of salt in the tank at any time t ≥ 0 is

s(t) = 1800 - 1750 exp(-t/150)

To find the time it takes for the tank to hold 100 lb of salt, solve for t in

100 = 1800 - 1750 exp(-t/150)

1700 = 1750 exp(-t/150)

34/35 = exp(-t/150)

ln(34/35) = -t/150

t = -150 ln(34/35) ≈ 4.348

So it would take approximately 4.348 minutes.

By the way, we didn't have to solve for s(t), we could have instead stopped with

-150 ln|1800 - s| = t + C

Solve for C - this C is not the same as the one we found using the other method. s(0) = 50, so

-150 ln|1800 - 50| = 0 + C

C = -150 ln|1750|

==>   t = 150 ln(1750) - 150 ln|1800 - s|

Then s(t) = 100 lb when

t = 150 ln(1750) - 150 ln(1700)

t = 150 ln(1750/1700)

t = 150 ln(35/34)

t ≈ 4.348

Answer:

cd a gimem ?

Step-by-step explanation:

Answer:

2

Step-by-step explanation:

because ther is in the picture

Answer:

Area= 452.23 ft²

Step-by-step explanation:

Angle at U = 180-48-20

Angle at U = 112°

UT/sin 112=46/sin 48

UT= 0.9272*46/0.7431

UT=57.4 ft

UV= sin 20*46/sin48

UV= 0.3420*46/0.7431

UV= 21.2 ft

S=( 21.2+57.4+46)/2

S=124.6/2

S= 62.3

Area= √((62.3)(62.3-21.2)(62.3-57.4)(62.3-46))

Area= √((62.3)(41.1)(4.9)(16.3))

Area= √204509.5311

Area= 452.23 ft²

Answer:

The choose C. 2

Step-by-step explanation:

[tex]slope = \frac{y2 - y1}{x2 - x1} \\ = \frac{ - 2 + 4}{3 - 2} = \frac{2}{1} = 2[/tex]

Answer:

option C is correct

Step-by-step explanation:

Hope it is helpful....

Answer:

1)9 2)18 3)9. 4)4. 5)carpeting

Step-by-step explanation:

1) divide 63 by 7 = 9

2)multiply 54 by 2 = 108 total weight of the boxes then divide 108 by 6 to get 18

3) 75 -30 to get remaining amount which is 45 then divide by 5 to get how much he will pay each month which is 9

4 24- 12= 12 the remaining for the 3 and divide by 3 to get 4

5) multiply 6 * 9 which is $54 which is cheaper than the $81

Answer:

see explanation

Step-by-step explanation:

He wants to buy at least 4 snacks , that is can be more than 4 , so

x + y ≥ 4

He only has $20 , thus total cost must be less than or equal to $20 , so

3x + 2y ≤ 20

Answer:

30.9 cm²

Step-by-step explanation:

To find the surface area of this figure, we find the area of the base and the 3 identical sides.

The base is split into two identical right triangles. Let's find the area of one and multiply by two.

Half of 3: 1.5

[tex]1.5\cdot2.6=3.9\\3.9\div2=1.95[/tex]

There are two right triangles:

[tex]1.95\cdot2=3.9[/tex]

The area of one of the sides will be the same thing, except the height is 6.

[tex]1.5\cdot6=9\\9\div2=4.5\\4.5\cdot2=9[/tex]

There are 3 sides identical to this one:

[tex]9\cdot3=27[/tex].

Add 27 and 3.9:

[tex]27+3.9=30.9[/tex]

Hope this helped!

Answer:

30.9 square centimeters

Step-by-step explanation:

3 * 1/2(3)(6) + 1/2(3)(2.6) = 30.9

Answer:

x=4

Step-by-step explanation:

it's a identity function because it is in the form of f(x)= x ,so the value of x is 4.

Answer:Astrid needs 280 tons of wood

Step-by-step explanation:

Because:

1 ship requires 40 tons of wood=accomodates 300 sailors

We must:

2100, sailors needed to be accomodated

÷

300, sailors that can be accomodated by 1 ship that requires 40 tons of wood

=7 groups of 300 sailors that can be accomodated by 1 ship that requires 40 tons of wood.

So:

I ship that requires 40 tons of wood × the 7, groups = 280 tons of wood.

I hope this helps! Im sorry its too complicated.

Simplier:

2100 ÷ 300= 7

40 × 7= 280

Answer:

280 tons of wood or 10 ships

Step-by-step

khan academy

Answer:

1. -y

3. 9a-7

5. 14x-2

7. 7d-6

Step-by-step explanation:

1. 8y-9y=-y

3. 8a-6+a-1

=(8a+a)-(6+1)

=9a-7

5. -x-2+15x

=(-x+15x)-2

=14x-2

7. 8d-4-d-2

=(8d-d)-(4+2)

=7d-6

Answer:

1. -x

3. 9a-7

5. 14x-2

7. 7d-6

Step-by-step explanation:

To do the first one you would just subtract 8 by 9 which is -1 so you would get -x as 1.

To do the third one would would just move the numbers around so you get 8a+a-6-1 and when you simplify you get 9a-7.

To do the fifth one you just have to move the numbers so you get -x+15x-2 and when you simplify you get 14x-2

To do the seventh one you just have to move the numbers so you get 8d-d-4-2 and when you simplify you get 7d-6.

Answer:

1533

Step-by-step explanation:

73x21= 1533

Answer:

73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73+73

=73x21=1533

Step-by-step explanation:

Answer:

65.94 square inches

Step-by-step explanation:

Surface area of a cone=πr(r+√h^2+r^2)

π=3.14

r=diameter/2

=14/2

=7 in

h=?

h=a

To find h using Pythagoras theorem

c^2 = a^2 + b^2

14^2 = a^2 + 7^2

14^2 - 7^2= a^2

196-49=a^2

147=a^2

Square root both sides

√147=√a^2

12.12=a

a=12.12 in

Surface area of a cone=πr(r+√h^2+r^2)

=3.14(7+√12.12^2+7^2)

=3.14(7+√147+49)

=3.14(7+√196)

=3.14(7+14)

=3.14(21)

=65.94 square inches

Answer:

y = - [tex]\frac{1}{16}[/tex](x - 1)² + 2

Step-by-step explanation:

Any point (x, y) on the parabola is equidistant from the focus and the directrix.

Using the distance formula

[tex]\sqrt{(x-1)^2+(y+2)^2^}[/tex] = | y - 6 |

Square both sides

(x - 1)² + (y + 2)² = (y - 6)² ( expand the factors in y )

(x - 1)² + y² + 4y + 4 = y² - 12y + 36 ( subtract y² - 12y from both sides )

(x - 1)² + 16y + 4 = 36 ( subtract 4 from both sides )

(x - 1)² + 16y = 32 ← subtract (x - 1)² from both sides )

16y = - (x - 1)² + 32 ( divide all terms by 16 )

y = - [tex]\frac{1}{16}[/tex] (x - 1)² + 2

Answer:

[tex]\displaystyle x=\left \{\frac{2\pi}{3}+2\pi k,\frac{4\pi}{3}+2\pi k, \frac{8\pi}{3}+2\pi k, \frac{10\pi}{3}+2\pi k\right \}k\in \mathbb{Z}[/tex]

Step-by-step explanation:

Hi there!

We want to solve for [tex]x[/tex] in:

[tex]4\sin^2(\frac{x}{2})=3[/tex]

Since [tex]x[/tex] is in the argument of [tex]\sin^2[/tex], let's first isolate [tex]\sin^2[/tex] by dividing both sides by 4:

[tex]\displaystyle \sin^2\left(\frac{x}{2}\right)=\frac{3}{4}[/tex]

Next, recall that [tex]\sin^2x[/tex] is just shorthand notation for [tex](\sin x)^2[/tex]. Therefore, take the square root of both sides:

[tex]\displaystyle \sqrt{\sin^2\left(\frac{x}{2}\right)}=\sqrt{\frac{3}{4}},\\\sin\left(\frac{x}{2}\right)=\pm \sqrt{\frac{3}{4}}[/tex]

Simplify using [tex]\displaystyle \sqrt{\frac{a}{b}}=\frac{\sqrt{a}}{\sqrt{b}}[/tex]:

[tex]\displaystyle \sin\left(\frac{x}{2}\right)=\pm \sqrt{\frac{3}{4}},\\\sin\left(\frac{x}{2}\right)=\pm \frac{\sqrt{3}}{\sqrt{4}}=\pm \frac{\sqrt{3}}{2}[/tex]

Let [tex]\phi = \frac{x}{2}[/tex].

[tex]\displaystyle \sin(\phi)=\frac{\sqrt{3}}{2},\\\phi = \frac{\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\phi =\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z}[/tex]

Therefore, we have:

[tex]\displaystyle \frac{x}{2}=\phi = \frac{\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\frac{x}{2}=\phi =\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z},\\\\\begin{cases}x=\boxed{\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z}},\\x=\boxed{\frac{4\pi}{3}+2\pi k , k \in \mathbb{Z}}\end{cases}[/tex]

[tex]\displaystyle \sin(\phi)=-\frac{\sqrt{3}}{2},\\\phi = \frac{4\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\phi =\frac{5\pi}{3}+2\pi k, k\in \mathbb{Z},\\\begin{cases}x=\boxed{\frac{8\pi}{3}+2\pi k, k\in \mathbb{Z}},\\x=\boxed{\frac{10\pi}{3}+2\pi k , k \in \mathbb{Z}}\end{cases}[/tex]

Answer:

x + y + z = 4

Step-by-step explanation:

Give equations are,

2x + 3y - z = 5 --------(1)

x - 3y + 2z = -6 --------(2)

3x + y - 4z = -8 --------(3)

By adding equations (1) and (2),

(2x + 3y - z) + (x - 3y + 2z) = 5 - 6

3x + z = -1 -------(4)

By multiplying equation (3) by 3, then by adding to equation (2)

(9x + 3y - 12z) + (x - 3y + 2z) = -24 - 6

10x - 10z = -30

x - z = -3 --------- (5)

By adding equation (4) and (5),

(3x + z) + (x - z) = -1 - 3

4x = -4

x = -1

From equation (5),

-1 - z = -3

z = 2

From equation (1),

2(-1) + 3y - 2 = 5

-2 + 3y - 2 = 5

3y = 5 + 4

y = 3

Therefore, x + y + z = -1 + 3 + 2

x + y + z = 4

Answer:

100.66 is the decimal.

Step-by-step explanation:

100⅔ = 302/3

302 ÷ 3 = 100.66 to infinity.

Answer:

division involves 5 steps:

D Divide

M Multiply

S Subtract

B Bring down

R Repeat or Remainder

Step-by-step explanation: i hope it helped