Solve the system of equations using elimination. 2x + y = 9 8x – 2y = 6

2 answers:

7 0

2x+y=9 (*2) __ 4x+2y=18 name it 1. 8x-2y=6 name it 2. Now add both equations, 1 & 2. 4x+2y+8x+-2y=18+6. 2y will be cancelled out. You'll be left with 12x=24, x=2. Then replace the value of x which is 2 in either equation 1 or 2. I'll go with 1 equation 4(2)+2y=18 2y=18-8=10 y=5. Using the equation 2 should provide the same result of y.

givi [52]4 years ago

3 0

For the first equation:
Let's solve for x.2x+y=9Step 1: Add -y to both sides.2x+y+−y=9+−y2x=−y+9Step 2: Divide both sides by 2.2x/2=−y+9/2x=−1/2y+9/2Answer:x=−1/2y+9/2

For the second equation:
Let's solve for x.8x−2y=6Step 1: Add 2y to both sides.8x−2y+2y=6+2y8x=2y+6Step 2: Divide both sides by 8.8x/8=2y+6/8x=1/4y+3/4Answer:x=1/4y+3/4
Hope I helped!:)

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