1. Solving Rational Equations
Lesson 7.5
Solving Rational Equations

2. “Clear an equation of fractions” by multiplying
each side of equation by LCD.
Multiply both sides of
equation by 35.
Check solution

3. fraction = fraction cross multiply

4. Multiply both
sides by 4
Add 36 to both
sides
Add x to both
sides

6. Check solution
x = 4 makes the
denominator = 0.
No Solution

8. Applications--Work-Rate Problem
With only the cold water valve open, it takes 8 minutes to fill the tub of a washing machine. With both the hot and cold water valves open, it takes only 5 minutes. How long will it take the tub to fill with only the hot water valve open?
rate for cold + rate for hot = rate for warm