Question

21. x²-6x+8=0
22. ¹+12x+20=0
23. x²-x-12-0
24. x²+2x-35=0

Answer 1

Ответ:

21)x²-6x+8=0

a=1;b=-6;c=8

D=b²-4×a×c=36-4×1×8=36-32=4

x=(-b±√D)/2a

x1=(6-2)/2=2

x2=(6+2)/2=4

22)a=1;b=12;c=20

D=144-80=64

x1=(-12-8)/2=-10

x2=(-12+8)/2=-2

23)a=1;b=-1;c=-12

D=1+48=49

x1=(1-7)/2=-3

x2=(1+7)/2=4

24)a=1;b=2;c=-35

D=4+140=144

x1=(-2-12)/2=-7

x2=(-2+12)/2=5