# The sum of two numbers is 15. One number is twice as large as the second number. What are the two numbers? Which let statement would you use?

Apr 27, 2018

$y = 5$
$x = 10$

#### Explanation:

Let $x$ be a number and let $y$ be the other number:
$x + y = 15$
$x = 2 y$

Substitute $2 y$ for $x$:
$2 y + y = 15$
$3 y = 15$

$y = 5$
$x = 10$