7x + 6y = -1 ; -x + 2y = 3 with elimination

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

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

x=30

step-by-step explanation: