Question

Solve (1/3y + 2)² = 121

Answer 1

First thing you must do is square root both sides. This gives you:

1/3y + 2 = √121 which becomes 1/3y + 2 = 11 and 1/3y + 2 = - 11

This is because both 11 and - 11 when squared are equal to 121. So we must solve for both to find the solutions. 

1/3y + 2 = 11

Subtract 2 from both sides to get 1/3y = 9

Now multiply both sides by 3 to isolate the variable y

3(1/3y) = 9(3) which becomes y = 27.

Now for the other equation 1/3y + 2 = - 11

Again, subtract 2 from both sides to get 1/3y = - 13

And multiply by 3 to isolate the variable y

3(1/3y) = - 13(3) which becomes y = - 39

Your answer: y = - 39, 27