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Solve the system by substitution

Solve the system by substitution-example-1
User RWendi
by
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1 Answer

6 votes

Answer:

(-5, -30)

Explanation:

We start with the equation:

y = 6x

y = -4x - 50

Since both of them are equal to y, we can substitute the 6x into y. So:

6x = -4x - 50

Now we can solve for x. Add 4x to both sides...

6x = -4x - 50

+4x +4x

10x = -50

Now, divide both sides by 10.

10x = -50

10 10

x = -5

So, we now know that x is -5. Now we know this, we can substitute -5 where we see x. It works in both equations, so I will do both.

y = 6(-5)

y = -30

And...

y = -4(-5) - 50

y = 20 - 50

y = -30

As you can see, both equations show that y = -30. To check our work, let's plug in the values.

-30 = 6(-5)

-30 = -30

Also:

-30 = -4(-5) - 50

-30 = -20 - 50

-30 = -30

So, we can see that both of the equations gave us the same answer. So, our answer is x = -5 and y = -30, so the ordered pair is: (-5, -30). Hope this helps you!

User Alex Parker
by
5.8k points