Question

Tolong jawab no 15 beserta caranya

Answer 1

2x - 3y = 18
x + 4y = -2 => kali 2 biar ada yang sama

2x - 3y = 18
2x + 8y = -4
dikurangiiii, x abis
-11y = 22
y = 22/-11
y = -2

lalu cari x menggunakan persamaan yg mana saja.
2x - 3y = 18
2x - 3(-2) = 18
2x + 6 = 18
2x = 18 - 6
2x = 12
x = 12/2
x = 6

jadi, x + y = 6 + (-2) = 6 - 2 = 4 (A)

Answer 2

2x-3y=18. (x1)
x+4y=-2. (x2)

2x-3y=18
2x+8y=-4
-------------- --
-11y=22
y=22/-11 = -2

x+4y=-2
x+4(-2) = -2
x+ (-8) = -2
x = -2 +8= 6

x+y= 6 +(-2) =4 (a)