Final answer:
Simplifying an expression with given substitutions involves replacing variables with their values and performing arithmetic operations to find a simpler form or a single number, following the order of operations.
Step-by-step explanation:
To simplify an expression with given substitutions means to replace variables in an algebraic expression with their corresponding values and then perform the operations to get a single number or a simpler expression.
For example, if you have the expression 2x + 3y and you are given the substitutions x=4 and y=1, you would replace x with 4 and y with 1 to get 2(4) + 3(1). Then you would multiply and add to simplify the expression: 8 + 3 = 11.
It's important to follow the order of operations when simplifying expressions. This means you should first address any parentheses or brackets, then exponents, followed by multiplication and division from left to right, and finally addition and subtraction from left to right.