The side of retangular floor are xm and (x + 7)m.the diagonal is (x + 8)m,calculate the value of x

Answer 1

using phythagoras theorm
(x+8)^2=x^2+(x+7)^2
x^2+16x+64=x^2+x^2+14x+49
16x+64=x^2+14x+49
x^2+14x-16x+49-64=0
x^2-2x-15=0
(x+3)(x-5)=0
x=5........