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Solve the following system of equations: 2x - y =7, 3x + 4y = -6

1 Answer

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Answer:

(2, -3)

Explanation:

You must choose from the 3 ways to solve the system of equations:

1. Substitution

2. Elimination

3. Graphing (least recommended)

My example is going to be substitution, as folllows:

2x - y = 7

(Add y to both sides)

2x = y + 7

(Subtract 7 from both sides)

y = 2x - 7

Now, we are able to use substitution in the next equation with the other equation!

3x + 4y = -6

(Replace y with what y equals -- other equation)

3x + 4(2x -7) = -6

(Simplify the parantheses)

3x + 8x - 28 = -6

(Add 28 to both sides)

3x + 8x = -6 +28

3x + 8x = 22

(CLT - Combine like terms)

11x = 22

(Divide 11 from both sides)

x = 2

Now, we will find what y is by plugging x into the other equation.

y = 2x - 7

x = 2

y = 2(2) - 7

y = 4 - 7

y = -3

y = -3

x = 2

Since we found both of the variables' values, we found our coordinate pairs to solve this equation!

Answer: (2, -3)

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