.Which equation will result if the substitution method is used to solve the following system of linear equations?

x – y = 7
x = y + 3

Question

.Which equation will result if the substitution method is used to solve the following system of linear equations?

x – y = 7
x = y + 3

anonymous · Answer

Simple substitute x = y + 2 in place of y in first equation and thats ur answer

studygurl14 · Answer

x - y = 7
x = y + 3
(y + 3) - y = 7

anonymous · Answer

Thanks! exactly what i thought!

studygurl14 · Answer

You're welcome. :)

anonymous · Answer

what about this one? ...Solve the following system of equations by linear combination:

5x + 2y = 14
y = x – 7

studygurl14 · Answer

Only one question per thread, please. But for this one, you want to eliminate a varibale in order to be able to solve the other one.

anonymous · Answer

Ok :)

studygurl14 · Answer

5x + 2y = 14
y = x - 7 --> y - x = -7  ->  -y + x = 7  -> x - y = 7

Now you have:
5x + 2y = 14
x - y = 7

anonymous · Answer

Thank you!

studygurl14 · Answer

Looks like it will be easy to eliminate the "y" varible

studygurl14 · Answer

x - y = 7  --> 2x - 2y = 14

studygurl14 · Answer

Now you have:
5x + 2y = 14
2x - 2y = 14
_____________

add those two equations ^ Can you do the rest from here?

anonymous · Answer

would it be (-3,4) ?

anonymous · Answer

?? is that wrong?

studygurl14 · Answer

No, sorry, but that is incorrect.