1)(1/2;1/3)
x1+x2=1/2+1/3=5/6 U x1*x2=1/2*1/3=1/6
корни уравнения x²-5/6x+1/6=0 и <span>6х^2-5x+1=0</span>
2)(11;7)
x1+x2=18 U x1*x2=77
3)(4/3;-5/4)
x1+x2=4/3-5/4=16/12-15/12=1/12
x1*x2=-5/3
корни уравнения 12х^2-x-20=0
-у = 5-3х
у = 3х-5.......................
<span>(5-6x)(5+6x)-25(1-3x)
</span>25-36*x^2-25+75х
75*x-36*x^2