122+z2=202

Raise 12 to the power of 2.

144+z2=202

Raise 20 to the power of 2.

144+z2=400

Subtract 144 from both sides of the equation.

z2=400-144

Subtract 144 from 400.

z2=256

z2=256

Take the square root of both sides of the equation to eliminate the exponent on the left side.

z=±256

Simplify the right side of the equation.

Rewrite 256 as 162.

z=±162

Pull terms out from under the radical, assuming positive real numbers.

z=±16

z=±16

The complete solution is the result of both the positive and negative portions of the solution.

First, use the positive value of the ± to find the first solution.

z=16

Next, use the negative value of the ± to find the second solution.

z=-16

The complete solution is the result of both the positive and negative portions of the solution.

z=16,-16

z=16,-16

z=16,-16

Solve for z 12^2+z^2=20^2