Question

G) {2x+y=10
{3x-2y=1


H) {2x+y=5
{2x+3y=2

i) {x+y=-3
{x-3y=-3

Answer 1

G) {2x+y=10 .(2)
{3x-2y=1

{4x+2y=20
{3x-2y=1
= 7x = 21
x = 21/7 = 3
2.3+y=10
y=10-6 = 4

H) 2x+y=5 .(-1)
= {-2x - y = -5
{2x + 3y = 2
= 2y = -3
y= -3/2
-> 2x + 3.(-3/2) = 2
-> 2x + (-9/2) = 2 .(2)
-> 4x - 9 = 4
-> x = 13/4

i) x = -3 -y

-> -3 -y -3y = -3
-> -4y = 3-3
-> y = 0
-> x + 0 = -3
-> x = -3