10 * 2x = 20x
3 * 15 = 45
When facing a multiplication of two fractions, you can simply multiply both numerators together and both denominators together. You'll end up having one fraction, that you can eventually simplify.
20x/45 = 4x/9
Trying to help my little brother through this particular problem but im stumped. In the book it says the correct answer is , ive gone through all the rest of his example problems but have been able to solve them successfully.