can you help me with my math homework?

Question

Jess spent 7x minutes on the computer. Her sister spent 5x + 10 minutes on the computer, which was the same amount of time Jess spent. How many minutes was Jess on the computer?

Answer 1

Here's what we know:

7x = 5x + 10 (Jess and her sister spent the same amount of time on the computer, so the two expressions equal one another)

We need to isolate x, so we need to start by subtracting 5x from both sides:

7x - 5x = 5x + 10 - 5x

2x = 10

Divide both sides by 2:

2x / 2 = 10 / 2

x = 5

 

Now that we know x, we can find their times:

7 * 5 = 5 * 5 + 10

35 = 25 + 10

35 = 35