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3 years ago

3x plus y equals 17 4x - y equals 18

1 answer:

8 0

3x+y=17
4x-y=18

4x-y=18
subtract 18 from both sides
4x-y-18=0
add y to both sides
4x-18=y
subsitute 4x-18 for y in first equation

3x+(4x-18)=17
7x-18=17
add 18 to both sides
7x=35
divide both sides by 7
x=5

subsitute
y=4x-18
y=4(5)-18
y=20-18
y=2

x=5
y=2

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Hi!

<u>Given these two equations:</u>

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<u>Learn more about the substitution (and also elimination!) method here:</u>

brainly.com/question/14619835

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3 years ago

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kotykmax [81]

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