The equations is 1 over 16 x to the 3rd minus x to the second minus 1 over 5 x to the second plus 3 over 8 x to the third plus 1 over 16 x to the 3rd and it says to collect like terms.

I hope this is what the question looked like Let me know if it isn't. But I'm sure this it will be similar and you can use this to guide you through: Simplifying Similar Expressions.png

Just remember whenever you have the same variables with the same exponents in an expression you can add the coefficients (numbers in front of these similar terms) to form one common term