Final answer:
In pyramid style combining like terms, one should start from the bottom and work upwards, which makes 'a' the correct answer.
Step-by-step explanation:
When combining like terms in a pyramid style, the correct strategy is typically to start from the bottom and move upward. This approach allows you to combine smaller groups of like terms together before summing the resulting terms with others above them.
So, the answer key for the question on combining like terms pyramid style would be:
- a) Combine terms from the bottom up