The best option is A) d - 90.
Expressions has no equal sign nor an inequality symbol. An expression has only standard or normal numbers, with variables and some basic mathematical operations.
PEMDAS (order of operations rules) require that we perform operations in a certain order: anything inside parentheses first, followed by any exponentiation, followed by mult. and div., finally followed by addition and subtraction.
Thus, we must evaluate 5+8÷4-1 first, as it's inside parentheses. Focusing on the division first, we get 5+8÷4-1 = 5 + 2 - 1, or 6.
Then we have 5 - [6], which comes out to -1.
Answer: x = 22
Step-by-step explanation: Since x is unknown, we want to isolate it and determine what it equals. We know that x - 3 gives us 19, but we don't want to know what x - 3 is, just x. So we can add three to both sides of the equation, to get our answer and keep it balanced. As a result, we get x = 22
