5(2x + 3)

review the distributive property
5(2x) + 5(3) = ______

i don't understand the x

it's just the name of a variable; its value is unspecified.
If you just want to expand the expression, the result is
5(2x + 3) = 10x+15

looks like you have some studying to do ...

10x + 15

thanks ✨sara✨

and oobleck