Identify ALL sets of LIKE terms!
2x and 3y
hr^2 and h^2r
wz and zw
2x^3 and 19x^3
21m^3y^4 and -9m^3y^4
5z and -3z
5x^3y^6 and 2x^6y^3

Question

Identify ALL sets of LIKE terms!
2x and 3y
hr^2 and h^2r
wz and zw
2x^3 and 19x^3
21m^3y^4 and -9m^3y^4
5z and -3z
5x^3y^6 and 2x^6y^3

anonymous · Answer

Like terms are two or more terms that are represented by the same variable(s) and raised to the same power. So, $$x ^{2} and 4x ^{2}$$ are like terms. Because both have the single variable x and a degree of 2 (aka raised to a power of 2). $$x ^{2} and x ^{2}y$$ are not like terms because the the first only has the variable x, while the second has both the variable x and y. 

Another way you can think of like terms is "which terms can I add together?" $$x^{2} + x^{2} = 2x^{2}$$ because we have two of the same term. However $$x^{2} + x$$ cannot be added together without first having a real number value for x. 

Think you can figure it out from there or still need some help?