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4 years ago

Solve the system of equations using elimination. 4x - 7y = 5 9x – 7y = –15

Mathematics

1 answer:

Anni [7]4 years ago

8 0

Step-by-step explanation:

We have to get one positive 7y so,

4x-7y=5

9x-7y=-15

multiply anyone of the equation by -1. I choose the first one so,

4x+7y=-5

9x-7y=-15

we can now cancel the y's so the equation will be left with

-4x=-5

9x=-15

add the equations

5x=-20

divide by 5 n u get

x=-4

now plug in the x value in any one of the

equations

I choose the first one so,

4(-4)-7y=5

-16-7y=5

add 16 to both sides

-7y=21

divide by -7

y=-3.

finally check.

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3 years ago

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Answer:

Step-by-step explanation:

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3 years ago

Factor this polynomial expression. x^2-16

V125BC [204]

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3 years ago

Petrolyn motor oil is a combination of natural oil and synthetic oil. It contains 8 liters of natural oil for every 5 liters of

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Answer: 370 liters

Step-by-step explanation:

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Also, the amount of petrolyn oil is proportional to the amount of synthetic oil.

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3 years ago

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BigorU [14]

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I think that’s the answer

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