The second of two numbers is 5 more than twice the first. The sum of the numbers is 44. How do you find the numbers?

1 Answer
Sep 25, 2015

x = 13
y = 31

Explanation:

You have two unknown numbers, we shall name them x and y.

Then we look at the information about these unknowns that is given, and write them out to get a picture of the situation.

The second number, which we have called y, is 5 more than twice the first. To represent this, we write
y = 2x + 5
where 2x comes from 'twice the first', and
+5 comes from '5 more'.

The next piece of information states that the sum of x and y is 44. We represent this as x+y = 44.

Now we have two equations to work off.

To find x, substitute y = 2x + 5 into x+y = 44.
We then get
x + (2x + 5) = 44
3x + 5= 44
3x = 44 - 5
3x = 39
x = 39/3
x = 13

Now we know the value of x, we can use it to find y.
We take the 2nd equation, and plug in x=13.
x+y = 44
13+y = 44
y = 44-13
y = 31