Question

Represent the following sentence as an algebraic expression, where "a number" is the letter x.

7 plus a number.

Answer 1

As Wikipedia says, "In mathematics, an algebraic expression is an expression built up from integer constants, variables, and the algebraic operations (addition, subtraction, multiplication, division and exponentiation by an exponent that is a rational number). For example, 3x^2 − 2xy + c is an algebraic expression."

7 + x is the algebraic expression you'd want.