x Solve the system of equations using elimination.

4x - 7y = 5
9x - 7y = -15
A
B
C
D
E
(3, 4)
(4,3)
(-3, 4)
(-4, 3)
(-4,-3)

1 answer

To solve the system of equations using elimination, we can subtract the first equation from the second equation to eliminate the y variable:

(9x - 7y) - (4x - 7y) = -15 - 5
9x - 7y - 4x + 7y = -20
5x = -20
x = -4

Now we can substitute x = -4 back into either of the original equations to find the value of y. Let's use the first equation:

4x - 7y = 5
4(-4) - 7y = 5
-16 - 7y = 5
-7y = 5 + 16
-7y = 21
y = -3

Therefore, the solution to the system of equations is (-4, -3).