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20 votes
20 votes
Solve by using substitution.=−3−3=−4−5

User Enenen
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1 Answer

22 votes
22 votes

hdhduxhx, this is the solution to the exercise:

Multiplying by -1 the second equation, we have:

y = -3x - 3

-y = 4x + 5

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0 = x + 2

x = -2

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Now we can solve for y in the first equation, this way:

y = - 3x - 3

y = -3 (-2) - 3

y = 6 - 3

y = 3

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Finally, let's prove that x = -2 and y = 3 is correct for the second equation, as follows:

y = -4x - 5

3 = -4 (-2) - 5

3 = 8 - 5

3 = 3

___________

We proved that x = -2 and y = 3 is correct.

User David Thorisson
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