Collecting Like Terms Flashcards

All 6 cards in this deck

What are like terms?

Terms with exactly the same letter or letters to the same power, e.g. $8h^3$ and $14h^3$.

What are the steps to simplify an expression by collecting like terms?

e.g. simplify $3x + 5y + 2x - 4y$

1. Group the like terms, keeping the sign in front of each: $3x + 2x$ and $5y - 4y$
2. Add or subtract the number parts: $5x$ and $y$
3. Write the simplified terms together: $5x + y$

True or false? $3x + 5y$ simplifies to $8xy$.

False. $3x$ and $5y$ are unlike terms, so $3x + 5y$ cannot be simplified.

True or false? $8h^3 + 14h^3 = 22h^6$.

False. It is $22h^3$ — you add the number parts and the power stays the same.

What are the steps to write an expression from a worded context?

e.g. 3 boxes with $x$ sweets each and 2 packets with $y$ sweets each

1. Write each part as a product: $3x$ and $2y$
2. Combine them as the words say (total means add): $3x + 2y$
3. Collect any like terms: already simplest, so $3x + 2y$

How do you find a formula for the total length $L$ of several labelled rods?

e.g. rods of length $a - 1$, $a$ and $a + 4$ cm

Add all the lengths and collect like terms: $a - 1 + a + a + 4$, so $L = 3a + 3$.