Question

Help me please.. no answers please...

Answer 1

So which method do you find easier and helpful for you to use.

Using the substitution method or elimination?

Answer 2

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

Answer 3

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

Answer 4

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

Answer 5

is that -4 or just 4?

Answer 6

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

Answer 7

im confused what doyou mean by plug it in?