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How do I solve 4x+y=-28;-3x+10y=21

User Mehmet Recep Yildiz
by
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1 Answer

22 votes
22 votes

Answer:

Answer:

x=−7 and y=0

Explanation:

Step: Solve4x+y=−28for y:

4x+y=−28

4x+y+−4x=−28+−4x(Add -4x to both sides)

y=−4x−28

Step: Substitute−4x−28foryin−3x+10y=21:

−3x+10y=21

−3x+10(−4x−28)=21

−43x−280=21(Simplify both sides of the equation)

−43x−280+280=21+280(Add 280 to both sides)

−43x=301 −43x

−43

=

301

−43

(Divide both sides by -43)

x=−7

Step: Substitute−7forxiny=−4x−28:

y=−4x−28

y=(−4)(−7)−28

y=0(Simplify both sides of the equation)

User Turning
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