Question

1.) 3x-y =4 dan 2x+3y =10 metode substitusi
2.) 4x+7y =17 dan 5x+3y =4 substitusi

Answer 1

3 x - y = 4   ⇒⇒⇒⇒ y = 3x - 4  pers. (3)
substitusi pers.(3) ke (2)
2x + 3y = 10
2x + 3(3x - 4) = 10
2x + 9x - 12 = 10
11x = 10 + 12
11x = 22
x = 2

substitusi x = 2 ke pers.(3)
y = 3x - 4
y = 3(2) - 4
y = 2
Hp: {2,2}


4x + 7y = 17 ⇒⇒⇒⇒⇒ 4x = 17 - 7y  ⇒⇒ x =    pers.(3)
substitusi pers.(3) ke (2)
5x + 3y = 4

 ⇒⇒⇒ masing-masing kali 4
85 - 35y + 12y = 16
-23 y = - 69
y = 3

substitusi y = 3 ke pers.(1)
4x + 7y = 17
4x + 7(3) = 17
4x = 17- 21
4x = -4
x = -1

Hp: {-1,3}