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The sum of two numbers is 67 and the difference is 13 . What are the numbers? PLEASE HELP IM NEW TO THIS AND WANT MY GRADES TO COME UP!!!!!!!!

1 Answer

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Answer:

The two numbers are 40, and 27.

Step-by-step explanation:

Since there are only two numbers, with two different aspects, you can just make

a system, and solve.

A sum of two numbers adding up to 67 can be modeled by: x + y = 67.

A difference of those same two numbers being 13 can be modeled by: x – y = 13.

You can add the two equations together to eliminate the y value because the -y and y will cancel out:

x + y = 67.

+ x – y = 13.

And you get: 2x = 80.

Now to find x, just divide by 2 on both sides to cancel out the coefficient of 2 in 2x:

2x = 80

÷2 ÷2

x = 40.

So the first number is 40.

Since we know the first number, we can immediately find the other number by substituting it into the first equation.

x = 40 → x + y = 67

(40) + y = 67

-40. -40

Subtract from both sides to cancel the constant terms.

Then you will get that y or the second number is y = 27.

This is true because 40 + 27 = 67, and 40 - 27 = 13.

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