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2 years ago

7.) Solve the system of equations below. -2x + 3y = 9 2/3x + 2y = 0

Mathematics

1 answer:

iren [92.7K]2 years ago

6 0

Answer:

So lets isolate y

we have

-2x+3y=9

2/3x +2y=0

Im gonna do the first equation

so -2x + 3y = 9

Add 2x on both sides

3y= 9+ 2x

Now divide by 3 to isolate y

y= 3+ 2/3x

Now we can subsitute y into any eqaution (I’m gonna do the second one) to solve.

2/3x+ 2(3+ 2/3x)= 0

Solve:

2/3x+ 6 + 4/3x = 0

6/3x +6= 0

2x+6=0

2x= -4

x= -2

Now we can subsitute this for any equation.

so I’m gonna do the first equation

-2(-2)+3y=9

4+3y=9

3y= 5

y= 5/3

y= 1 2/3

Final answer:

x=-2

y= 1 2/3

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