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2 votes
Y = 4x - 3
y =-2x + 9

1 Answer

3 votes
Answer is ( 2, 5 )

Step by step

To solve this system of equations, substitute the value of y from equation 1 in for y in equation 2. They will equal each other.

4x -3 = -2x + 9
Add 2x to both sides to combine variables

4x + 2x -3 = -2x + 2x + 9
Simplify

6x -3 = 9
Add 3 to both sides to combine constants

6x -3 +3 = 9 + 3
Simplify

6x = 12

Divide both sides by 6 to solve for x

6/6 x = 12/6

x = 2

Now sub the value of x = 2 into the first equation and solve for y

y = 4 (2) -3
y = 8 -3
y = 5

Your solution is ( 2, 5)

Or you can enter the two equations into a graphing calculator and find where the two lines cross, that is also your solution. See attachment
Y = 4x - 3 y =-2x + 9-example-1
User Scott Rossi
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