Question

求解几个方程 x²-5x-2=-8 x²-9x+

Answer 1

x²-5x 6=0.

1.-2

1.-3

(x-2)(x-3)=0.

x=2,x=3.

x²-9x 20=0

1.-4

1.-5

x-4)(x-5)=0.

x=4.x=5

4x^2 x 1=0.

b²-4ac=1-4*4*1=-15