5х+3х-3-6х-11=0
2х-14=0
2х=14
х=7/-7
X^2+8x+15=0
D=b2-4ac
D=8^2-4*1*15
D=64-60=4 под корнем
D=2
x=-b+-d/2a
x1=-8+2/2=-3
x2=-8-2/2=-5
6x+(3x-2)=14
6x+3x-2=14
9x=14+2
9x=16
x=16/9
x=1 7/9
8y-(7y-142)=51
8y-7y+142=51
y=51-142
y=-91
(6x+1)-(3-2x)=14
6x+1-3+2x=14
8x-2=14
8x=14+2
8x=16
x=2
(6-2x)+4=-5x-3
6-2x+4=-5x-3
-2x+10=-5x-3
-2x+5x=-3-10
3x=-13
x=-13/3
x=-4 1/3