Answer:

Step-by-step explanation:
-5(2x - 5) = 8 + (5 - 2x)
-10x + 25 = 8 + 3x
-10x - 3x = 8 - 25
-13x = -17
<u>x</u><u> </u><u>=</u><u> </u><u>1</u><u>7</u><u>/</u><u>1</u><u>3</u><u> </u><u>=</u><u> </u><u>1</u><u> </u><u>4</u><u>/</u><u>1</u><u>3</u>
Answer:
7. 
8. b. 
Step-by-step explanation:
7. Solve the equation

First, note that

Hence,

Use substitution

then

Now,

Solve each equation separately for 


8. b. Solve the equation

Rewrite it:

By zero product property,

Solve each equation separately.


Recall that density = mass / volume.
Let's plug our known values into the equation.
15 g/cm^3 = 360g / volume
First, let's multiply both sides by volume
Volume * 15 g/cm^3 = 360g
Divide both sides by 15 g/cm^3
Volume = 24 cm^3
Answer: The sales tax rate is 5%.
Step-by-step explanation: In order to calculate the sales tax rate you need to divide the amount of sales tax by the amount of the purchase. In this case you divide .20 by $4.00. .2 / 4 = .05 = 5% sales tax rate