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3) Solve this system using elimination method. Upload your work

8x + 14 y = 4
-6x - 7y=-10

User Slashmili
by
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1 Answer

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14 votes

Answer:

y = -2 and x = 4

Explanation:

8x + 14y = 4

-6x - 7y = -10

First, find the lowest common multiple of 8 and 6 (which is 24). Multiply the first equation by 3:

8x + 14y = 4

3(8x + 14y) = 3(4)

24x + 42y = 12

Multiply the second equation by 4:

-6x - 7y = -10

4(-6x - 7y) = 4(-10)

-24x - 28y = -40

Now, add the two equations together:

24x + 42y = 12

-24x - 28y = -40

24x + -24x = 0

42y + -28y = 14y

12 + -40 = -28

14y = -28

Divide both sides by 14:

14y ÷ 14 = -28 ÷ 14

y = -2

Plug this known variable back into the first equation:

8x + 14(-2) = 4

8x + (-28) = 4

8x - 28 = 4

Add 28 to both sides:

8x - 28 + 28 = 4 + 28

8x = 32

Divide both sides by 8:

8x ÷ 8 = 32 ÷ 8

x = 4

So y = -2 and x = 4.

Hope this helps!

User RavindUwU
by
2.5k points