kerjakan dengan metode eliminasi dan substitusi sertakan dgn caranya a.x+3y=1 5x+3y=19 b.6p-q=1 4p-3q+40-0 c.x-2y+1=0 2x+3y=16

bagian a
x + 3y = 1
5x+3y =19
________ _
-4x = -18
x = 9/2

substitusikan x = 9/2
x + 3y = 1
9/2 + 3y = 1
3y = 1 - 9/2
3y = -7/2
y = -7/6

jadi x = 9/2 dan y = -7/6

bagian b
6p-q =1 |×3
4p-3q = -40 |×1
____________
18p-3q = 3
4p-3q = -40
__________ _
14p = 43
p = 43/14

substitisikan p = 43/4
6p - q = 1
6(43/4)-q = 1
129/2-q = 1
-q = 1-129/2
-q = -127/2
q = 127/2

bagian c

x-2y = -1 | ×2
2x+3y=16
_________
2x-4y =-2
2x+3y=16
________ _
-7y = -18
y = 18/7

substitusikan y=18/7

x -2y =-1
x = -1+2y
x = -1+36/7
x = 31/7