Question

Solve the following system using the substitution method:
3x + y = -3
y = 2x + 7

Answer 1

Well it's already set up to use that method for you, so substitute y = 2x+7 into the first equation where y is.

3x(2x+7)=-3 and solve for x, then substitute x back into any of the original equations then solve for y.

Answer 2

is it inconsistent or dependent

Answer 3

I'm not sure, you'll have to do it to figure that out.

Answer 4

how

Answer 5

Well lets solve for x and see

Answer 6

iss it 1/4

Answer 7

\[3x+(2x+7)=-3\]

Answer 8

Oh ok, well if it's inconsistent you would get something like 0 = -3, dependent would be -3 = -3

Answer 9

This one seems to be dependent.

Answer 10

ok what about the coordinates

Answer 11

is there a solution

Answer 12

That's what we're trying to solve right now

Answer 13

oh ok

Answer 14

5x + 7=-3?

Answer 15

\[3x+2x+7 = -3 \implies 5x=-10 \implies x = -2\]

so we have x now,

lets solve for y,

\[y=2x+7 \implies y=2(-2)+7 \implies y = -4+7 \implies y = 3\]

So your coordinates are (-2,3) you can check if I did the algebra right.

Answer 16

thanks