1) 9 х+2y-4 = 0

{

8x+y-2=0

2) 5u+7v+3=0

{

10u-v+6=0

1) 9x+2 (2-8x) = 0 { y=2-8x

9x+4-16x=0 { y=2-8x

-7x=-4 { y=2-8x

x=4/5 { y=2-8 (4/5)

x=4/5 { y=2-32/5

x=4/5 { y=10/5 - 32/5

x=4/5 { y = - 22/5

x=4/5 { y = - 4,4

2) 5u+7 (6+10u) + 3=0 { v=6+10u

5u+42+70u+3=0 { v=6+10u

75u=-45 { v=6+10u

u=-0,6 { v=6+10*-0,6

u=-0,5 { v=0