r=2s-8

Rewrite the equation as 2s-8=r.

2s-8=r

Add 8 to both sides of the equation.

2s=r+8

Divide each term in 2s=r+8 by 2.

2s2=r2+82

Cancel the common factor of 2.

Cancel the common factor.

2s2=r2+82

Divide s by 1.

s=r2+82

s=r2+82

Divide 8 by 2.

s=r2+4

s=r2+4

Solve for s r=2s-8