How do you express the phrase "the sum of 13 and twice a number h" as an algebraic expression?
SUM in maths is the answer to an addition.
It is always used with the word AND to show which values are added together.
"Twice" means times by 2.
So, 13 and twice 'h' are being added together.
[Note that the following means something different:
"Twice the sum of 13 and h"
Here 13 and h are to be added, and the answer is doubled.