Tentukan nilai ( x. y) yang memenuhi persamaan: a. 2x + y = 5 X + 2y = 7 b. 2x - 3y = 12 3x + 4y = 1

A. 2x+y=5 |*1
x+2y=7 |*2
...............................
2x+y=5
2x+4y=14
................................-
-3y=-9
y=-9/-3
y=3
2x+y=5
2x+3=5
2x=5-3
2x=2
x=2/2
x=1
x=1 dan y=3

B. 2x-3y=12 |*3
3x+4y=1 |*2
.............................
6x-9y=36
6x+8y=2
...........................-
17y=34
y=34/17
y=2
2x-3y=12
2x-3(2)=12
2x-6=12
2x=12+6
2x=18
x=18/2
x=9
x=9 dan x=2