Respuesta :
that is a difference of two square numbers, we can factorize them easily:
0 =-b^2 + 25
b^2 - 25 = 0
(b + 5)(b - 5) = 0
0 =-b^2 + 25
b^2 - 25 = 0
(b + 5)(b - 5) = 0
0=-b^2+25
Add b^2 to both sides
0+b^2= -b^2+25+b^2
b^2= 25
Take square root
b= +_ square root 25
b= 5 or b = -5
I hope that's help !