Help me please.. no answers please...

Question

anonymous · Answer

attachment

zale101 · Answer

So which method do you find easier and helpful for you to use.

Using the substitution method or elimination?

anonymous · Answer

What ever one you think is easier to walk me through :)

zale101 · Answer

I'll use substitution.
To use this method, we first look at $\color{red} {one}$ of the equation -3y-4x=21 and 4x-y=7 and try to solve for one variable, either x or y.
I'll choose 4x-y=7  and I will solve for y

zale101 · Answer

4x-y=7
subtract -4x to both sides
-y=7-4x
divide by -1
y=-7+4x
y=4x-7

anonymous · Answer

is that -4 or just 4?

zale101 · Answer

now, we know that y is (4x-7), plug that to the y variable in the equation -3y-4x=21 
Can you do that?

anonymous · Answer

im confused what doyou mean by plug it in?

loser66 · Answer

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