Question

Follow the directions to solve the system of equations by elimination.

8x + 7y = 39

4x – 14y = –68

Multiply the first equation to enable the elimination of the y-term.
Add the equations to eliminate the y-terms.
Solve the new equation for the x-value.
Substitute the x-value back into either original equation to find the y-value.
Check the solution.
The solution to the system of equations is (
,
).

Answer 1

8x + 7y = 39
4x - 14y = -68

(multiply each term in second equation by -2)

8x + 7y = 39
-8x + 28y = 136

(add both equations)

35y = 175

(divide both sides by 35)

y = 5

(substitute value of y in one of the equations)

8x + 7(5) = 39
8x + 35 = 39
8x = 4
x = 1/2
(x, y) = (1/2, 5)