x = (x-42)^2
x=x^2 - 84x +1764
x^2 - 85x + 1764 = 0
D = 85^2 - 4*1*1764=7225 - 7056 = 169
x =( 85 +-13)/2= 49 ; 36.
x = (x-42)^2
x=x^2 - 84x +1764
x^2 - 85x + 1764 = 0
D = 85^2 - 4*1*1764=7225 - 7056 = 169
x =( 85 +-13)/2= 49 ; 36.