Respuesta :

Answer:

The solution for this question is  144.

Step-by-step explanation:

Given that

3+√x=√(x+81)   (i)

square equation (i)

(3+√x)^2=(√(x+81)^2

we know that (a+b)^2=(a^2+b^2+2.a.b).and√x*√x=(√x)^2=x So,

(3)^2+(√x)^2+2*3*√x=x+81

9+x+6√x=x+81

6√x=x+81-x-9

6√x=x-x+81-9   Simplify the equation.

6√x=72

√x=72/6

√x=12  (a)

square equation (a) for x value.

(√x)^2=(12)^2

x=144