For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

x − y = 8
−x − y = −7
----------------------

8 − y

−8 − y

8 + y

−8 + y

Question

For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

  x − y = 8
−x − y = −7
----------------------

 8 − y

 −8 − y

 8 + y

 −8 + y

mertsj · Answer

If you follow your directions, you will see that isolating x in the first equation gives you the equation :  x = 8+y and that is the expression you would subsitute for x in the second equation to solve by substitution.

mertsj · Answer

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