-21 = 15 - 2z^2

Holt McDougal Larson Algebra 1 Common Core Edition page 597 number 24

Asked by Dee Dee on 26 Mar 10:24

Last updated by anonymous on 27 Mar 11:23

Answered by CherieS on 27 Mar 11:23

-2z^2+15=-21

-2z^2+15-15=-21-15

-2z^2=-36

-2z^2/-2=-36/-2

z^2=18

z = 3 sqrt(2)