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Solve the following system of equations using SUBSTITUTION METHOD.

SHOW YOUR WORK for full points. Write your answer as an (x,y) point.

x = 4y - 1
3x + 2y =39

User Ancyrweb
by
4.8k points

1 Answer

3 votes
Multiply the 1st row by 3
3x−12y=−3
3x+2y=39

Subtract the 2nd row from the 1st row.
−14y=−42

Solve for y (-14y=-42)

Divide both sides by −14.

Y= -42/-14

Two negatives make a positive.
Y=42/14

Simply 42/14 to 3
Y=3

Sub y=3 into both equations
3x-12x3=-3
X=11

Therefore,
X =11
Y=3
User SilentNot
by
4.6k points