Question

Given that R = 3x + 9y

Find x when y = 6 and R=7
Give your answer as an improper fraction in its simplest form.​

Answer 1

Explanation:

R = 3x + 9y

They told us that R = 7, y = 6

So you can rewrite the equation as:

R = 3x + 9y

7 = 3x + 9(6)

7 = 3x + 54

Subtract 54 from both sides.

7 - 54 = 3x

-47 = 3x

To find x, you need to divide both sides by 3

3x = -47

x = -47/3