Объяснение:
d= 18^2 - 4 *65
d=324 - 260
d^2=64
d = 8;
x1 = -18 -8 /2 x1 = -13
x2 = -18 +8 /2 x2 = -5
x1 -x2 = -13 - (-5) = -13 +5 = -8
x1+x2 = -13 +(-5) = -18
x1 * x2 = -13 * (-5) = 65
