Jane has $20.00 to spend on $15.00 t-shirt and 2 pens. how much can she spend on each pen if they are both the same price?

Let p = cost of pens in dollars.

Jane has 20 dollars, she cannot go above this amount, so we should set up an equation.

This equation says the fifteen dollar shirt plus the 2 pens she buys has to be equal to $20.00. Let's solve this equation to find the price of the pens. First, we must subtract 15 from both sides. When we do that, we get:

After that, we must get p by itself, so divide both sides by 2.

When we divide and simplify, we get:

or

The cost of the pens are $2.50. If you want to check your work, plug in 2.50 for p.

This is true. Therefore, the answer is valid.