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3 years ago

14

How to solve for 6x+3y=21 3x-7y=2

1 answer:

Nastasia [14]3 years ago

3 0

Hi there!

We can solve this equation by using the systems of equations.

We can do this by subtracting like terms from both equations using substitution.

First, let's find the value of y:

6x + 3y = 21
3y = -6x + 21
y = -2x + 7

Then, we should plug it into one of the equations:

3x - 7y = 2
3x - 7(-2x + 7) = 2
3x + 14x - 49 = 2
17x = 51
x = 3

Now, we solve for y by plugging the value of x into the equation:

3x - 7y = 2
3(3) - 7y = 2
9 - 7y = 2
-7y = -7
7y = 7
y = 1

There's your answers.

Hope this helps!

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