3 years ago

Solve the system of equations by substitution. Write your solution as an ordered pair

2 answers:

8 0

Solving it by substitution is:

4(3y-20)+8y=20: substitute the second equation into the first equation (hence the name solving by substitution)
12y-80+8y=20: distribute 4 to 3y and 4 to 20
20y-80=20: combine like terms (12y+8y)
20y=100: add 80 to 20
y=5: divide 100 by 20 and you get 5

:)

marshall27 [118]3 years ago

5 0

Answer: (-5,5)

Step-by-step explanation:

graphing the two equations on a calculator gets the point (-5,5)

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