Systems of Equations - Solving by Substitution

[samanthafearce]

Hey! I need some help on these problems for PreCalc.

Its solving by substitution.

Please show me how to do this if you can.

1) -2x - 4y = 8
y = -4x - 2


2) -2x + 2y = 8
y = -4x - 1


Thanks!

 

[stapel]

Its solving by substitution.

Please show me how to do this if you can.

1) -2x - 4y = 8
y = -4x - 2

2) -2x + 2y = 8
y = -4x - 1

You already have loads of worked examples in your book, in your class notes, and online. Are you still unable even to get started? :shock:

 

[Bob Brown MSEE]

Substitute the value of y (in the second line) in place of y on the first line.


PS: It is a good idea to put parenthesis around the value of y as you do the above.