# Simplifying a Variable Expression

## Presentation on theme: "Simplifying a Variable Expression"— Presentation transcript:

Simplifying a Variable Expression
EXAMPLE 4 Simplifying a Variable Expression = 14x 7xy 2 7 x 7 x y Factor numerator and denominator. 1 2 7 x 7 x y = Divide out common factor. = 2 y Simplify.

Evaluating a Variable Expression
EXAMPLE 5 Evaluating a Variable Expression Evaluate the expression when x = 5. –4x3 2x –4x3 2x = – x x x 2 x Factor numerator and denominator. 1 – x x x 2 x = Divide out common factor. = –2x2 Simplify. = –2(5)2 Substitute 5 for x. = –50 Evaluate powers and simplify.

GUIDED PRACTICE for Examples 4 and 5 Simplify the variable expression. Then evaluate for x = – 2 and y = 3. 12. 4xy 6x = 2y 3 = 2

GUIDED PRACTICE for Examples 4 and 5 Simplify the variable expression. Then evaluate for x = – 2 and y = 3. 13. 32y 8xy = 4 y = 4 3

GUIDED PRACTICE for Examples 4 and 5 Simplify the variable expression. Then evaluate for x = – 2 and y = 3. 14. 3x3y 6x = x2y 3 = 4

GUIDED PRACTICE for Examples 4 and 5 Simplify the variable expression. Then evaluate for x = – 2 and y = 3. 15. 5x2y 10xy = x 2 = –1