Answer:
x= -1, y=1
Step-by-step explanation:
First label the 2 equations.
7x +6y= -1 -----(1)
-x +2y= 3 -----(2)
Then choose which term you would like to eliminate. To eliminate the y term, multiply equation (2) by 3 such that the coefficient of y is 6.
(2) ×3:
-3x +6y= 9 -----(3)
Since the coefficient of y is positive 6 in both equations, subtract one equation from the other.
(3) -(1):
-3x +6y -(7x +6y)= 9 -(-1)
Expand:
-3x +6y -7x -6y= 9 +1
-10x= 10
x= 10 ÷(-10)
x= -1
Substitute x= -1 into (2):
-(-1) +2y= 3
1 +2y= 3
2y= 3 -1
2y= 2
y= 2 ÷2
y= 1
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2nd method: eliminating the x term
(2) ×7:
-7x +14y= 21 -----(3)
Since the coefficient of y in equation (1) is a positive 7, while that in equation (3) is a negative 7, add the 2 equations together to eliminate the x term.
(1) +(3):
7x +6y -7x +14y= -1 +21
20y= 20
y= 20 ÷20
y= 1
Substitute y= 1 into (2):
-x +2(1)= 3
-x +2= 3
-x= 3 -2
-x= 1
x= -1
