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8x + 3y = 13
3x + 2y = 11

User Yadab
by
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1 Answer

2 votes

Answer:

x=-1, y=7 (-1,7)

Explanation:

Follow along in attached work.

1) Multiply both equations in order to eliminate a variable, in this case, y. After multiplying the top equation by 2, and the bottom equation by -3 (-3 instead of positive 3 because if it was positive, 6 and 6 would not cancel out, but 6 and -6 do cancel out), we have 16x+6y=26 and -9x-6y=-33. Cancel out the y values, and we're left with 16x=26 and -9x=-33.

2) Stack the equations and add them together (subtract is also an option but adding is simpler). On the left side of the equation, we're doing 16x-9x which equals 7x, and on the right side of the equation, we're doing 26-33 which equals -7. The current equation is 7x=-7. Divide both sides by 7 to isolate the variable. 7x/7=x, -7/7=-1. x=-1.

3) The final step is to plug in our x value into either of the equations. I chose the top equation.

8(-1) +3y=13.

-8+3y=13 (Add 8 to both sides, inverse of -8)

3y=21 (Divide both sides by 3 to isolate the variable)

3y/3=21/3

y=7

If this explanation doesn't make sense, make sure to look at the attached image.

8x + 3y = 13 3x + 2y = 11-example-1
User LearnerEarner
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