(3b-5)²-49= (3b-5)²-7²= (3b-5-7)*(3b-5+7)= (3b-12)*(3b+2)= 3*(b-4)(3b+2)
1)(24/6-15-18*2,4)=2
2)2/1,5=1,33
3х-у=-5] х 2
-5х+2у=13
6х-2у=-10
-5х+ 2у = 13(-2у і 2у скорочуються?)
0,01292831295 правильный ответ
a) 4 x ^2 - 8x -5 = 0D=64-4*4*(-5)=64+80=144
<span>SQRT(D)=12
х1=(8+12)/8=20/8=5/2
х2=(8-12)/8=-4/8=-1/2
b) 5x^2 + 16x - 3 = 0
</span>D=16^2-4*5*(-3)=256+60=316
SQRT(D)=SQRT(316)[
x1=(-16+SQRT(316))|10=(-16+SQRT(79*4))|10(-16+2*SQRT(79)|10=(2(-8+SQRT(79))|10=(-8+SQRT(79))|5
x2=(-16-SQRT(316))|10=(-16-SQRT(79*4))|10(-16-2*SQRT(79)|10=(2(-8-SQRT(79))|10=(-8-SQRT(79))|5