Question

What are the solutions to the equation y^2-1 = 80?

Answer 1

y2−1=80

Step 1: Add 1 to both sides.

y2−1+1=80+1

y2=81

Step 2: Take square root.

y=±√81

y=9 or y=−9

Answer:

y=9 or y=−9

Answer 2

y^2-1=80

y^2=81

y = positive and negative 9