Evaluating expressions

Evaluating Algebraic Expressions

How can you evaluate an algebraic expression?

substitution is the process of replacing a variable with a specific numerical value or another algebraic expression

La sustitución es el proceso de reemplazar una variable con un valor numérico específico u otra expresión algebraica.

Take Notes! - ¡Tomar apuntes!

Evaluating Expressions

Solve by substituting the variable with the value
Resolver sustituyendo la variable con el valor

evaluate/evaluar:

2x + 4y

x = 5

y = 2

replace the variable/ reemplazar la variable:

2 (5) + 4 (2)

Solve/ Resolver:

10 + 8 = 18

Example 1

• Replace values

• Simplfy/Solve

Ejemplo 1

• Sustituir valores

• Simplificar/Resolver

Multiple Choice

What does our following expression look like after substituting the variables if w = 5 and v = 3?

$$8w\ -\ 2v$$  

• $$8(3)-2(5)$$

• $$8(5)-2(5)$$  

• $$8\left(5\right)\ -\ 2\left(3\right)$$  

• $$8(3)-2(3)$$  

Fill in the Blanks

Evaluate/evaluar:

$8\left(5\right)-2\left(3\right)$  

Multiple Choice

Find the value of the following if a = 2.

$$10a-3$$  

• 23

• -23

• -17

• 17

Fill in the Blanks

Evaluate 8 - x

when x = -5

Evaluating Expressions

Solve in the parentheses first, then order of operations

replace the variable:

2(3 + 4) + 6

Solve:

2(7) + 6

14 + 6 = 20

evaluate/evaluar:

2(x + 4) + 6

x = 3

Resuelva primero los paréntesis y luego el orden de operaciones.

Multiple Choice

Evaluate when a = 15:
2(a - 5) + 2

• 22

• 27

• 14

• 7

Multiple Choice

Evaluate the expression.   Let g = 3    h = 9 
h² + 2g

• 27

• 87

• 24

• 17