Question

calcule o valor de z na equação z^2-25=(z+3)^2-28

Answer 1

$z^{2}-25= (z+3)^{2}-28 \\ \\ z^{2}-25= (z^{2}+2z*3 + 3^{2}) -28 \\ \\ z^{2}-25= z^{2}+6z + 9 -28 \\ \\ z^{2}-25= z^{2}+6z -19 \\ \\ z^{2} - z^{2} -6z = 25 -19 \\ \\ -6z=6 \\ \\ z= \frac{(-6)}{6} \\ \\ z=-1$