Question

x^2-3x-10=0 решите пожалуйста

Answer 1

D = b^2 - 4ac = (-3)^2 - 4*1*(-10) = 9 + 40 = 49 = 7^2
x1 = ( - b + √D)/2a = ( 3 + 7)/2 = 10/2 = 5;
x1 = ( - b - √D)/2a = ( 3 - 7)/2 = - 4/2 = - 2;