Question

What value of r makes the equation true
2(3r + 11) = (7r - 3r)

Answer 1

r=-11

Explanation:

Solve for r:

2 (3 r + 11) = 7 r - 3 r

7 r - 3 r = 4 r:

2 (3 r + 11) = 4 r

Expand out terms of the left hand side:

6 r + 22 = 4 r

Subtract 4 r from both sides:

(6 r - 4 r) + 22 = 4 r - 4 r

6 r - 4 r = 2 r:

2 r + 22 = 4 r - 4 r

4 r - 4 r = 0:

2 r + 22 = 0

Subtract 22 from both sides:

2 r + (22 - 22) = -22

22 - 22 = 0:

2 r = -22

Divide both sides of 2 r = -22 by 2:

(2 r)/2 = (-22)/2

2/2 = 1:

r = (-22)/2

2 | 1 | 1

| 2 | 2

- | 2 |

| | 2

| - | 2

| | 0:

Answer: r = -11