Answer:
(9, 5)
Step-by-step explanation:
Given the simultaneous equation;
-X + 9y = 36 .... 1
3x + 3y = 42 ... 2
Multiply equation 1 through by -1 to have;
x - 9y = -36 ....1
3x + 3y = 42 ... 2
From 1;
x = -36 + 9y ....3
Substitute equation 3 into 2;
3(-36+9y) + 3y = 42
Open the parenthesis
-108 + 27y + 3y = 42
-108 + 30y = 42
30y = 42 + 108
30y = 150
y = 150/30
y = 5
Substitute y = 5 into equation 3;
From 3;
x = -36 + 9y
x = -36 + 9(5)
x = -36 + 45
x = 9
Hence the solution to the system of equation is (9, 5)