Solve the system of equations by eliminating the y variable:

Feb 2016
377
10
seattle
Solve the system of equations by eliminating the y variable:
 

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Oct 2013
713
91
New York, USA
Multiply all three terms in the second equation by 2. Then add the two equations and you will be left with only x terms and constants.
 
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Feb 2016
377
10
seattle
Multiply all three terms in the second equation by 2. Then add the two equations and you will be left with only x terms and constants.
okay thanks so I get

3x+2y=-21
10x-2y=-22

then becomes 13x=43 so is my answer 43/13x?
 
Oct 2013
713
91
New York, USA
okay thanks so I get

3x+2y=-21
10x-2y=-22

then becomes 13x=43 so is my answer 43/13x?
No, because you need to multiply the -22 by 2. When multiplying an equation by a constant, make sure to multiply both sides of the equation.
 
Apr 2016
8
1
Europe
1. Multiply the second equation by 2

3x + 2y = -21
5x - y = -22

-->

3x + 2y = -21
10x - 2y = -44

2. Make it just one equation by solving the simultaneous equation

13x +2y - 2y = -65
13x = -65

3. Solve for x and y

13x = -65
x = -65/13
x = -5

Substitute into equation

5(-5) - y = -22
-25 - y = -22
-y = 3

y = -3

Overall:

x = -5
y = -3