Respuesta :

(9x^2+10x+c) = (3x+b)^2
= 9x^2 + 6b x+ b^2

1) 6b= 10
b+ 5/3

2) c=b^2
c= (5/3) ^2
c= 25/9

(9x^2+10x+25/9)=(3x+5/3)^2

I hope this helps:)