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Solve the following systems of linear equations using substitution

6x - y = -7 and 5x + y = -4

User Leviticus
by
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1 Answer

1 vote

Answer:

(-1,1)

Explanation:

1. Rearrange either equation to isolate one of the variables. Lets use 6x - y = -7 :

6x - y = -7

-y = -7 - 6x

y = 7+6x

2. Now use this definition of x in the second equation:

5x + y = -4

5x + (7+6x) = -4

11x = -11

x = -1

3. Now use x = -1 in either equation to find y:

6x - y = -7

6 (-1) - y = -7

-y = -1

y = 1

The solution is (-1,1)

See the attached graph.

Solve the following systems of linear equations using substitution 6x - y = -7 and-example-1
User Harry Ninh
by
7.1k points