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Solve the system of equations by the addition method 3x - 2y = 79x + 4y = 16

User KatieK
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1 Answer

3 votes

ANSWER

x = 2, y = -0.5

Step-by-step explanation

We have two equations in the system of equations:

3x - 2y = 7

9x + 4y = 16

To use the addition method, we have to make the coefficients of one variable in one equation, the same as in the second equation.

Let us make the coefficient of y the same in the two equations.

We do that by multiplying the first equation by 2:

2(3y - 2y) = 2(7)

=> 6y - 4y = 14

Now we have:

6y - 4y = 14

9x + 4y = 16

Add them together:

6x - 4y = 14

+ (9x + 4y = 16)

=> 15x + 0 = 30

=> 15x = 30

x = 30 / 15

x = 2

Put that in the first equation:

3x - 2y = 7

3(2) - 2y = 7

6 - 2y = 7

=> 2y = 6 - 7

2y = -1

=> y = -1/2

y = -0.5

Therefore, x = 2, y = -0.5

User Amatya
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6.1k points