A)
6(y-x)-50=y ; 6y-6x -50 - y =0; 6x =5y-50;
y-xy=24; 6y -6xy =144;6y-(5y-50)y =144; 6y-5y^2+50y =144; 5y^2-56y+144=0
D = (-56)^2 -4*5*144=256
y1 =1/10 (56-16) =4; x1 = (5*4-50)/6 = -5
x = - 5; y =4
y2 =1/10 (56+16) =36/5; x1 = (5*36/5-50)/6 = -7/3
x= -7/3; y =36/5
б)
p+5t=2(p+t); p+5t -2p -2t =0 ;3t -p=0; p=3t
pt-t=10;3t*t-t=10; 3t^2 -t -10 =0
D = 1-4*3*(-10)=121
t1= 1/6 (1-11)= - 5/3; p = 3*(-5/3) = -5 ;
p=-5 ; t = -5/3
t2= 1/6 (1+11)= 2; p=3*2= 6
p= 6; t = 2