LCM of Algebraic Expressions

The moment you try to add two algebraic fractions with different denominators — say (1)/(2x) + (1)/(3y) — you hit a wall until you can find their common denominator. That common denominator is nothing more than the least common multiple of the two bottoms. You already know how to find the LCM of ordinary numbers; this lesson stretches that same skill to expressions with letters and powers. Get it right, and adding fractions, solving equations that hide denominators, and simplifying messy expressions all become routine — right through your O/L paper.