
Daniel A. answered 10/11/12
Experienced and Patient Math Tutor for All Ages
When we know what a variable equals, namely that c=5 and d=2, we can replace them with those values in the equations. So:
2cd/2c = 2(5)(2)/2(5) = (2 × 5 × 2) ÷ (2 × 5) = 20 ÷ 10 = 2
Don't forget that saying 2cd over 2c is the same as saying 2cd divided by 2c