Question

Sorry for being a pain :D
Use the substitution method to solve the following system of equations.

4x − y = 3
7x − 9y = −2

(1, 1)

(6, −3)

(6, 1)

(1, −3)

Answer 1

Add y to both sides, then subtract 3 from both sides to isolate y in the first equation. Doing so gives:

y = 4x - 3

The expression for y can be substituted into the second equation:

7x - 9y = -2

and after substitution we have

7x - 9(4x - 3) = -2

Now we simplify and solve for x:

7x - 36x + 27 = -2
(7 - 36)x + 27 = -2
-(36 - 7)x + 27 + 2 = 0
-(29)x + 29 = 0
29 = 29x
29/29 = x
1 = x

Now plug the value for x back into the one of the original equations to get y.

Answer 2

I don't know how to get the Y... that's why im asking for help..

Answer 3

Do I do it the same way you got x?

Answer 4

We isolated y earlier to get

y = 4x - 3

If we substitute x = 1 into that equation, we get y.

Answer 5

Oh.. so its D

Answer 6

(1, -3)

Answer 7

y = 4(1) - 3
y = 4 - 3
y = 1

Therefore, the point is (1,1)

Answer 8

Im confused

Answer 9

Re-read it all over again, but slowly.