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Solve the system of equations.
2x + 9y = 6

-7x - 8y = -21

User ThomasH
by
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1 Answer

9 votes

Answer: y=0 and x=3

Step 1: Solve for x in 2x+9y=6.


2x+9y=6


2x=6-9y (Subtract 9y from both sides)


x=3 - 4.5y( Divide both sides by 2)

Step 2: Replace x with 3-4.5y


-7x - 8y = -21\\-7(3-4.5y) - 8y = -21\\

Step 3: Solve for y


(-21)+31.5y-8y=(-21) (By looking at this, we can determine that y=0)

Step 4: Replace y with 0


2x+9y=6\\2x+9(0)=6\\2x=6\\


x=3 (Divide both sides 2)

Therefore, y=0 and x=3