X+y=10 and 2x+4y=30What are the steps to solve this equation?

Mathematics

1 answer:

Ronch [10]3 years ago

6 0

Answer:

x=5 and y=5

Step-by-step explanation:

You "plug" one equation into the other, to get a new equation that only has one variable (x or y), then you can simplify that and have your answer.

So let's plug the first into the second:

First, we convert the first equation into an x=... form. For this one, this means moving the +y to the other side:

x = 10 - y

Now we substitute 10-y for x in the second equation:

So 2x+4y=30 becomes:

2(10-y) + 4y = 30

And simplify that:

20 - 2y + 4y = 30

20 + 2y = 30

2y = 30-20

2y = 10

y = 5

This is the first answer! If we put this into the first equation, we get:

x = 10 - 5 = 5

Now we have both answers, x=5 and y=5

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