Question

(x-7) (x-3) + 10x = 30

Answer 1

(x-7).(x-3) +10x= 30

x^2-3x-7x+21+10x=30

x^2 -10x +10x +21= 30

x^2 +21= 30

x^2= 30-21
x^2= 9
x= +ou -√9
x'= +√9= 3 e x"= -√9=-3