Question

How do I solve this system of equations? Help ASAP!

-4x+9Y=9
X-3Y=-6

Answer 1

-4x+9Y=9
X-3Y=-6
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(Solve x-3y=-6 for x)
Add 3y to each side
x - 3y + 3y = -6 + 3y
x = 3 y - 6
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Substitute 3y - 6 for x in -4x + 9Y = 9
-4(3y-6)+9y=9
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Simplify
-3y+24=9
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Add -24 on each side
-3y+24+-24=9+-24
-3y=-15
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Now divide each side by -3
-3y ÷ -3 = -15 ÷ -3
y = 5
Now you have Y!
Now we find X
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Substitute 5 for y in x=3y-6
x=(3)(5)-6
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Simplify
x = 9
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X = 9 and Y = 5 are your answers

Answer 2

-4x + 9y = 9...............(1)
x - 3y = -6 Multiply through by 3:-
3x - 9y = -18..............(2)

adding equations (1) and (3):-

-x = -9

x = 9

Substitute for x in equation (1)
-4(9) + 9y = 9
-36 + 9y = 9
9y = 45
y = 5

Answer is x = 9 and y = 5