James is 10 years less than twice as old as Brandon. If the sum of their ages is 56, what are their ages?

Question

I don't know what equation I am supposed to use to find this out.

Answer 1

Here's what we know:

2b - 10 = j (James is 10 years less than 2 times Brandon's age)

b + j = 56 (their ages total 56)

 

We have a value for j, so plug it in:

b + 2b - 10 = 56

Simplify:

3b - 10 = 56

 

To solve the above equation, just add 10 to both sides, then divide both sides by 3, isolating b. You can then place b in the either of the above equations to find James' age.