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Which ordered pair satisfies the system of equations below?

X - 2y = 1
X + 4y = 7

A. (-3,1)
B. (3,-1)
C. (-3,-1)
D. (3,1)

PLEASE HELP ♡

1 Answer

4 votes

Answer:

D. (3,1)

Explanation:

To solve a pair of equations using substitution, first solve one of the equations for one of the variables. Then substitute the result for that variable in the other equation.


x-2y=1,x+4y=7

Choose one of the equations and solve it for x by isolating x on the left hand side of the equal sign.


x-2y=1

Add 2y to both sides of the equation


x=2y+1

Substitute 2y+1 for x in the other equation, x+4y=7.


2y+1+4y=7

Add 2y to 4y.


6y+1=7

Subtract 1 from both sides of the equation


6y=6

Divide both sides by 6.


y=1

Substitute 1 for y in x=2y+1. Because the resulting equation contains only one variable, you can solve for x directly.


x=2+1

Add 1 to 2.


x=3

The system is now solved.


x=3,y=1

I hope this heps you

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