How many liters of a 35% salt solution must be mixed with 20 liters of 70% salt solution to obtain a solution that is 45% salt? What is the equation?

Answer:

Q2: -17

Q3: a) -5/2  b) g = -13

Step-by-step explanation:

2w+7 = -9

2w = -9 - 7

w = -16/2

w = -8

---

15 - 4w

= 15 - 4(-8)

= 15 - 32

= -17

----------------------

Q3:

a) 3/4(16m-24) = -48

16m -24 = -48 ÷ 3/4

16m = -64 + 24

16m = -40

m = -5/2

b) -20 = 1/6(36+12g)

-20 = 1/6 × 6(6+2g)

(cross out the 6 from 1/6 and 6)

-20 = 6 + 2g

-20-2g= 6

-2g = 6+20

-2g = 26

g = 26/-2

g = -13

Answer:

96 dollars and 50 cents

Step-by-step explanation:

Answer:

C. Point A lies on ray BC

Step-by-step explanation:

Points A and C can be connected by a segment which would be a measure of the distance between the points. Locating point B between AC, makes the three points lying on segment AC.

A ray extends from a point to infinity, a line extend to infinity on both sides, while a segment is known to have two endpoints. Therefore, points AC are the end points of the segment AC, and point B between this segment confirms that point B lies on the segment AC. Therefore, Point A lies on ray BC is not correct.

Answer:

=x(x-1) +3x

= x^2-x+3x

=x^2 +2x

=x(x+2)

Step-by-step explanation:

Answer:

15. 6444.44445

14. 484

Step-by-step explanation:

Answer:

The derivative of the function f(x) = -5x+3x is ---->  -2

Step-by-step explanation:

Answer:

Step-by-step explanation:

I'm assuming you are trying to solve for x. I'm not sure, but that's what I figured out for the answer, so I'm gonna go with that. : )

We are looking for the value of x to make that statement true. It's going to take some trig manipulations, but if you are at this level of precalc, these identities should definitely NOT be new to you. We will begin by squaring both sides of that equation to get:

[tex]9sin^2(x)+3cos^2(x)=3[/tex]

From here we will factor out a 3 to get:

[tex]3(3sin^2x+cos^2x)=3[/tex] and then divide both sides by 3 to get:

[tex]3sin^2x+cos^2x=1[/tex]

Knowing the Pythagorean identity for the trig ratios, we will replace the sin-squared with what it is equal to in terms of cos-squared. If:

[tex]sin^2x+cos^2x=1[/tex], then

[tex]sin^2x=1-cos^2x[/tex]. Making that replacement gives us an equation with only one trig ratio in it, namely, cos:

[tex]3(1-cos^2x)+cos^2x=1[/tex] and distributing:

[tex]3-3cos^2x+cos^2x=1[/tex] which simplifies down to:

[tex]-2cos^2x=-2[/tex]. Divide both sides by -2 to get:

[tex]cos^2x=1[/tex]. When you take the square root of both sides you get:

[tex]cos(x)=1[/tex] and [tex]cos(x)=-1[/tex]. Here is where we will use the unit circle to see where the cos is 1 and where the cos is -1. You didn't give me an interval in which to work, so I am going to use from 0 degrees to 180. Within that interval, the cos is 1 at 0 degrees; within that interval, the cos is -1 at 180.

Now we need to plug those values into the original equation to see if they work. One of them may be extraneous. Plugging in 0 first:

3sin(0) + √3cos(0) = -√3. We need to see if this is true.

The sin of 0 is 0; the cos of 0 is 1, so

0 + (√3)(1) = -√3?

The left side is √3, not -√3, so 0 doesn't work. Let's try 180 now, shall we?

3sin(180) + √3cos(180) = -√3. We need to see if this is true.

The sin of 180 is 0; the cos of 180 is -1, so

0 + (√3)(-1) = -√3?

The left side is -√3 and so is the right side, so

x = 180°

Answer:

3 / 19

Step-by-step explanation:

Given the following :

ratio of college graduates with a graduate degree to non-college graduates = 1:8

ratio of college graduates without a graduate degree to non-college graduates is 2:3

If college graduate with a degree = A

College graduate without a degree = B

Non-college graduate = C

College graduate to non college graduate = A:C

College graduate without degree to non college graduate = B:C

A:C = 1:8 - - - (1) ; B:C = 2:3 - - - (2)

Combining the two ratios :

To do so : the proportion of non college graduate should be the same in both ratios

To do this, multiply (1) by 3 and (2) by 8

A:C = 3 : 24

B:C = 16 : 24

combining both, we have :

A:B:C = 3:16:24

If one random college graduate is picked, what is the probability that they hold a graduate degree?

Total proportion of college graduate : (college graduates with degree + college graduates without degree)

A + B = (3 + 16) = 19

Proportion who hold a graduate degree = A = 3

Probability = require outcome / Total possible outcomes

Thus :

P = A / (A +B)

= 3/19

Answer:

6 and 14

Step-by-step explanation:

let the second number=x

the first number=3x-4

(x+3x-4)+5=25

4x-4+5=25

4x+1=25

4x=25-1

4x=24

x=6

Since x is the first number,the first number is 6

second number=3•6-4

=18-4=14

Answer:

There are seven seventh roots of unity, e2πki7 , all on the unit circle, r=1 above.

The first one is at θ=2π7=360∘7=5137 ∘ , and there are others at 4π7,6π7,8π7,10π7,12π7 and of course at 0 radians, i.e. unity itself.

How to find?

There are 4 fourth roots of unity and they are 1, i,−1 and−i

Each of the roots of unity can be found by changing the value of k k k in the expression e 2 k π i / n e^{2k\pi i/n} e2kπi/n. By Euler's formula, e 2 π i = cos ⁡ ( 2 π ) + i sin ⁡ ( 2 π ) = 1.

here is the answer for question ii

Answer:

s - t = 10 - -7 = 17

Step-by-step explanation:

I only see

s - t

nothing else is there to evaluate (or calculate).

s - t = 10 - -7 = 17 (as a double "-" always turns into a "+").

you really needed help with that ?

Answer:

= s-t

= 10 - (-7)

= 10 + 7

= 17

✌✌✌✌

Answer:

The correct answer is

Step-by-step explanation:

11 square centimeters.

Hope this helps....

Have a nice day!!!!

Answer:

Step-by-step explanation:

Amount charges by plumber =  £ 167.00

Call out fee = £ 18.50

Charge excluding the call out fee = 167 - 18.50 = £ 148.50

Total hours worked = 9 hours

Charge per hour = charge excluding the call out fee ÷ total hours

                           = 148.50 ÷ 9

                          = £ 16.50

Answer:

son2: 5

son1: 10

Step-by-step explanation:

2x (son1) + x (son2) + 35 (mother) + 3 (years)*3 (people) = 59

3x = 15

x = 5

The age of each boy at present will be 2 years and 3 years.

A linear system is one in which the parameter in the equation has a degree of one. It might have one, two, or even more variables.

Let the age of the sons will be x and y.

A mother who is 35 years old has two sons, one of whom is twice as old as the other. Then the equation will be

x = 2y

In 3 years, the sum of all their ages will be 59 years. Then the equation will be

x + y + x + 1 + y + 1 + x + 2 + y + 2 + 35 = 59

Simplify the equation, we have

3x + 3y + 41 = 59

      6y + 3y = 59 – 41

              9y = 18

                y = 2

Then the value of x will be

x = 2y

x = 2(2)

x = 4

Thus, the age of each boy at present will be 2 years and 3 years.

More about the linear system link is given below.

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Answer:

Step-by-step explanation:

=-5 +4

= -1

put a dot on -1 and go from -5 to -1 and then from -1 to -5

Answer:

Step-by-step explanation:

Given the expression 4sinB = 3sin(2A+B), we are to show that the expression 7cot(A+B) = cotA

Starting with the expression

4sinB= 3sin(2A+B)

Let us re write angle B = (A + B) - A

and 2A + B = (A + B) + A

Substituting the derived expression back into the original expression ww will have;

4Sin{(A + B) - A } = 3Sin{(A + B)+ A}

From trigonometry identity;

Sin(D+E) = SinDcosE + CosDSinE

Sin(D-E) = SinDcosE - CosDSinE

Applying this in the expression above;

4{Sin(A+B)CosA - Cos(A+B)SinA} = 3{Sin(A+B)CosA + Cos(A+B)sinA}

Open the bracket

4Sin(A+B)CosA - 4Cos(A+B)SinA = 3Sin(A+B)CosA + 3Cos(A+B)sinA

Collecting like terms

4Sin(A+B)CosA - 3Sin(A+B)cosA = 3Cos(A+B)sinA + 4Cos(A+B)sinA

Sin(A+B)CosA = 7Cos(A+B)sinA

Divide both sides by sinA

Sin(A+B)CosA/sinA= 7Cos(A+B)sinA/sinA

Since cosA/sinA = cotA, the expression becomes;

Sin(A+B)cotA = 7Cos(A+B)

Finally, divide both sides of the resulting equation by sin(A+B)

Sin(A+B)cotA/sin(A+B) = 7Cos(A+B)/sin(A+B)

CotA = 7cot(A+B) Proved!

Answer:

3 chocolate bars and 2 graham crackers

Step-by-step explanation:

8 times 3 equals 24

12 times 2 equals 24

Answer:

7A-42

Step-by-step explanation:

Answer:

The anwser is C) C < 4

......... .

Answer:

y=-5/6

Step-by-step explanation:

-24y=20

y=-5/6

alternate:

-0.83

Part A

Her steps were

[tex]-2 \frac{5}{6} \div 1 \frac{1}{3}\\\\-\frac{17}{6} \div \frac{4}{3}\\\\-\frac{6}{17} \times \frac{3}{4}\\\\-\frac{6\times 3}{17\times4}\\\\-\frac{18}{68}\\\\-\frac{9}{34}\\\\[/tex]

Kelsey made a mistake on line 3. Note how the 17/6 flips to 6/17. This is not correct. You keep the first fraction the same, but you do flip the second fraction. This only applies when you divide two fractions.

The third step should look like [tex]-\frac{17}{6}\times \frac{3}{4}[/tex]

=======================================================

Part B

Here's what she should have written

[tex]-2 \frac{5}{6} \div 1 \frac{1}{3}\\\\-\frac{17}{6} \div \frac{4}{3}\\\\-\frac{17}{6} \times \frac{3}{4}\\\\-\frac{17\times 3}{6\times 4}\\\\-\frac{51}{24}\\\\-\frac{17}{8}\\\\[/tex]

If you want to convert that improper fraction to a mixed number, then you could do something like this

[tex]-\frac{17}{8} = -\frac{16+1}{8}\\\\-\frac{17}{8} = -\frac{16}{8}-\frac{1}{8}\\\\-\frac{17}{8} = -2 \frac{1}{8}\\\\[/tex]

Or you could divide 17 over 8 using long division to get 2 remainder 1. The 2 is the quotient that goes to the left of the 1/8. The remainder of 1 is the numerator of 1/8.

The equation with exactly one solution is  3x + 5 = 2x - 6. Option D is correct.

To determine which equation has exactly one solution, we need to solve each equation and see if we end up with a unique value for 'x'.

4x – 4 + 2x = 6x - 4

Combine the x terms on the left side: 6x - 4 = 6x - 4

This equation is an identity and holds true for all values of x. It doesn't have a unique solution.

B. 2(4x + 5) = 8x + 10

Distribute the 2 on the left side: 8x + 10 = 8x + 10

Similar to the previous equation, this equation is also an identity and holds true for all values of x.

It doesn't have a unique solution.

4x - 8 = 4(x - 4)

Distribute the 4 on the right side: 4x - 8 = 4x - 16

Subtract 4x from both sides: -8 = -16

This equation is contradictory and has no solution.

3x + 5 = 2x - 6

Subtract 2x from both sides: x + 5 = -6

Subtract 5 from both sides: x = -11

This equation has a unique solution, x = -11.

So, the equation with exactly one solution is  3x + 5 = 2x - 6. Option D is correct.

To learn more on Equation click here:

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Answer: I think it would be C

Step-by-step explanation:

Answer:

the correct answer is C because its the only polygon with a caved in feature

Answer:

Hey there!

Part A. This is a proportional relationship because the amount of dollars she earns per hour is constant. We can divide her total income by the number of hours she works to find that she earns 12.50 dollars per hour.

Part B. Joslyn will always earn more money than Kate because she earns more money per hour, and the slope of Joslyn's line is greater.

Let me know if this helps :)

Answer:

cot α = 1/tan α = 1/2.4 = 0.42

Step-by-step explanation:

cot α=0.42

sin α = 0.92

we know that  cot α = 1/tan α

thus,

cot α = 1/tan α = 1/2.4 = 0.42

we know that

sin(x)=tan(x)1+tan2(x)√

[tex]\ sin(\alpha )=tan(\alpha )/\sqrt{ 1+tan^2(\alpha )} \\sin(\alpha )= 2.4/\sqrt{1+2.4^2} = 2.4/\sqrt{1+5.76}\\sin(\alpha )= 2.4/\sqrt{6.76} = 2.4/2.6 = 12/13 = 0.92[/tex]

sin α = 0.92

Answer:

A. x + 100x/y

Step-by-step explanation:

Machine A= x hours longer to produce 660 widget than machine B

Machine B produces y% more widget per hour than machine A

let

b = Number of hours it takes Machine B to make 660 widgets.

Time taken for Machine A to make the 660 widgets = x + b.

Rate of Machine B = 660/b

Rate of Machine A = 660 / (x + b).

Machine B produces y% more widgets per hour than Machine A:

660 / (x + b)(1 + y/100) = 660/b

1 / (x + b)(1 + y/100) = 1 / b

Multiply both sides by (x+b)

1 + y/100 = (x + b)/b

1 + y/100 = x/b + 1

Subtract 1 from both sides

y/100 = x/b

Take the inverse of both sides

100/y = b/x

Make b the subject

100x/y = b

b=100x/y

The time taken for Machine A to make the 660 widgets is x + b = x + 100x/y.

Answer is A. x + 100x/y

[tex]\dfrac{DI}{DR}=\dfrac{DE}{DZ}\\\\\dfrac{DI}{6+2.8}=\dfrac{3}{6}\\\\6DI=26,4\\DI=4,4[/tex]

Answer:

x=2

Step-by-step explanation:

3(x+2) = 12

Divide by 3

3/3(x+2) = 12/3

x+2 = 4

Subtract 2 from each side

x+2-2 = 4-2

x =2

Answer:

The value of x is equal to 2.

Step-by-step explanation:

3(x + 2) = 12

Distribute 3 to (x + 2)

3x + 6 = 12

Subtract 6 from both sides of the equation.

3x = 6

Divide 3 on both sides of the equation.

x = 2

The value of x is 2