(2х-1)(15+9х)-6х(3х-5)=87 (14х-1)(2+х)=(2х-8)(7х+1) (х+10)(х-5)-(х-6)(х+3)=16 (3х+7)(8х+1)=(6х-7)(4х-1)+93х

1)30X+18x^2-15-9x-18x^2+30x=87 51x-15-87=0 51x=15+87 51x=102 x=2 2)28x+14x^2-2-x=14x^2+2x-56x-8 28x+14x^2-2-x-14x^2-2x+56x+8=0 81x+6=0 81x=-6 x=-2/27 3)x^2+5x-50-x^2-3x+6x+18=16 8x-32=16 8x=16+32 8x=48 x=6 4)24x^2+3+56x+7=24x^2-6x-28x+7+93x 24x^2+3+56x+7-24x^2+6x+28x-7-93x=0 0=0