Vocabulary
A letter that represents an unknown number.
Una letra que representa un número desconocido.
What is a variable?
¿Qué es una variable?
How many "term families" are in the expression below?
–15x + 32 + 3.5y – 19 + 2x – 0.5x
3 families
x, numbers, and y
The order of operations used to evaluate an expression.
El orden de las operaciones utilizadas para evaluar una expresión.
What is PEMDAS?
John puts $320 in the bank from his birthday, every week he takes out $3.89 for breakfast for x week. Write an expression to show how much money John has left.
320– 3.89x
Are the expression 3x + 5 and 5 – 3x equivalent?
Show your work
Yes
A number or variable separated by a + or – sign.
Un número o variable separados por un signo + o -.
What is a term?
¿Qué es un término?
Combine like terms.
21x + 3 – 10x – 2x +20 +3
9x + 26
Evaluate 4x – 5, when x = 2
3
20 + 0.3x
Are the expressions –1.2 x + 9 + 3.2 x and 4x + 9 equivalent?
Show your work.
No
The words "split" or "quotient" means this operation.
Las palabras "dividir" o "cociente" significan esta operación.
What is division?
¿Qué es la división?
Combine like terms
3x2 – 4x + x + 12x2 –7 – 25x2
–10x2 –3x –7
Evaluate – 3.2x2 + 2x – 3, when x = 3
–25.8
Brianna wants to buy apples, they are $0.79 per pound. She also needs blue berries, they are $2.99 per pound. Write an expression to show how much money she will spend on apples (a) and blueberries (b)?
0.79a + 2.99b
Show your work!
No
To substitute or replace a variable with a number.
Para sustituir o reemplazar una variable con un número.
What is simplify?
¿Qué es simplificar?
Combine like terms.
1.5y – 3z + 21 – 5.2y +3 + z – x2
–3.7y – 2z + 24 – x2
Evaluate 2y2 – 7x + 3, when y= 0.3 and x = (1/2).
–0.32
A whale was swimming at 21 feet below sea level. He decides to swim down 2 feet every hour. Write an expression to show how far below sea level the whale will be after h hours.
–21 – 2h
Is 8x2 + 2y equivalent to –14x + 6y2 when x = 1 and y = 2?
Show your work.
Yes
To replace a variable with given number.
Para reemplazar una variable con un número dado.
What is evaluate?
¿Qué es evaluar?
Combine like terms
3y2 + 15xy – 5 + 4y – 18xy + 7y – 6y2 + xy – y2
–4y2 – 2xy – 5 + 11y
–88
An airplane is cruising at 5,000 feet above sea level. In order to land, he has to descend at a rate of 20 feet per minute. Write an expression to show how far above sea level the plane is after m minutes.
5,000 – 20m
Which expressions are equivalent to 9x3 + y2 – 21
a) –y2 + 9x3 –21
b) –21 + 9x3 + y2
c) y2 + 9x3 – 21
d) –y2 – 9x3 + 21
B and C