A) (2x-5y-6=0 (3x-4y-2=0 {2x-5y-6=0 {3x=5y+6/ 3 { 2x-5y-6=0 {x=5/3y+2 {2*(5/3y+2)-5y-6=0 {x=5/3y+2 {10/3y+4-5y-6=0 {x=5/3y+2 {-50/30y-2=0 {x=5/3y+2 {-50/30y=2 / -(50/30) {x=5/3y+2 {y=-3 1/3 {{x=5/3*10/3+2 {{y=-3 1/3 {{x=5/3*(-10/3)+2=-50/90 +2=1 40/90 B (3y+5x=0 (3x+2y=0 {3y=-5x/ 3 {3x+2y=0 {y=-5/3x {3x+2*(-5/3)=0 {{y=-5/3x {3x-10/3=0 {{{y=-5/3x {3x=10/3 /3 {x=10 {y=-5/3*10=-50/3 c) (7x+8y=9 (5x+6y=7 {7x=-8y+9 (5x+6y=7 {x=-8/7y+9/7=1/7y 5*1/7+6y=7 5/7+6y=7 x=1/7y 6y=7-5/7 x=1/7y 6y=44/7 /6 {y=37 5/7 {x=1/7*264/7=264/49
a) 2x-5y-6=0 3x-4y-2=0 2x=5y+6/2 3x-4y=2 x=5/2y+3 3(5/2y+3)-4y=2 x=5/2y+3 15/2y+9-4y=2 x=5/2y+3 3i1/2y=-7 /:(7/2) x=5/2y+3 y=-2 x=5/2*(-2)+3 y=-2 x=-2 y=-2 SPR 2x-5y-6=0 2*(-2)-5*(-2)-6=0 -4+10-6=0 6-6=0 0=0 L=P b)3y+5x=0 3y+5x=0 3x+2y=0 3y=-5x/:3 3x+2y=0 y=5/3x 3x+2*5/3x=0 y=5/3x 3x+3i1/3x=0 y=5/3x 6i1/3x=0/:6i1/3 y=5/3x x=0 y=0 x=0 SPR 3y+5x=0 3*0+5*o=0 0=0 L=P c) 7x+8y=9 5x+6y=7 7x=9-8y/:7 5x+6y=7 x=9/7-8/7y 5(9/7-8/7y)+6y=7 x=9/7-8/7y 45/7-40/7y+6y=7 x=9/7-8/7y 2/7y=4/7 /:(2/7) x=9/7-8/7y y=2 x=-1 y=2 SPR 7x+8y=9 7*(-1)+8*2=9 -7+16=9 9=9 L=P
