What are the answers and work for 15, 18, and 21

To solve equations such as the ones you listed above, our end goal is to isolate the variable (the letter that represents an unknown value).

Let’s begin with Number 15.

a/5 - 2 = 9

Due to the reverse order of operations, we should first add 2 to both sides of the equation.

a/5 = 11

To solve, we should multiply both sides by 5 to get rid of the denominator on the variable a.

a = 55 (answer)

Next, we can move onto number 18.

2/3g + 6 = -12

To solve this equation, we should begin by subtracting 6 from both sides.

2/3g = -18

Next, we can get the variable g alone by multiplying both sides by 3/2 (this will cancel out the coefficient of 2/3 on the variable g).

g = -27 (answer)

Finally, we can solve number 21 in a similar manner.

(c-5)/4 = 3

To solve this problem, we should first multiply both sides by 4 to get rid of the denominator on the variable c.

c - 5 = 12

To finish our simplification, we should add 5 to both sides of the equation to get the variable c completely alone.

c = 17 (answer)

Therefore, your answers to questions 15, 18, and 21, are 55, -27, and 17, respectively.

Hope this helps!

answer: a and b

step-by-step explanation: