2(6x^2+15x-2x-5)-6(2x^2+4x-x-2)=48
2(6x^2+13x-5)-6(2x^2+3x-2)=48
12x^2+26x-10-12x^2-18x+12=48
8x+2=48
8x=48-2
8x=46
x=46/8
x=5.75
ответ: x=5.75.
x^2+3.5x-2=0
D=(3.5)^2-4*1*(-2)=12.25+8=20.25=4.5
x1=4.5-3.5/2=1/2=0.5
x2=4.5+3.5/2=8/2=4
ответ: x1=0.5, x2=4.
2(6x^2+15x-2x-5)-6(2x^2+4x-x-2)=48
2(6x^2+13x-5)-6(2x^2+3x-2)=48
12x^2+26x-10-12x^2-18x+12=48
8x+2=48
8x=48-2
8x=46
x=46/8
x=5.75
ответ: x=5.75.
x^2+3.5x-2=0
D=(3.5)^2-4*1*(-2)=12.25+8=20.25=4.5
x1=4.5-3.5/2=1/2=0.5
x2=4.5+3.5/2=8/2=4
ответ: x1=0.5, x2=4.