PSAT Math : How to subtract rational expressions with different denominators

Study concepts, example questions & explanations for PSAT Math

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : How To Subtract Rational Expressions With Different Denominators

Simplify.

Possible Answers:

Correct answer:

Explanation:

Determine an LCD (Least Common Denominator) between  and .

LCD = 

Multiply the top and bottom of the first rational expression by , so that the denominator will be .

Distribute the  to .

Now you can subtract because both rational expressions have the same denominators.

Final Answer. 

Learning Tools by Varsity Tutors