Download 16 - Solving Rational Functions

16 ­ Solving Rational Functions ­ Day 2
November 18, 2016
Solving Rational
Equations - 2
Bell Work
Make sure you are seated and quiet with the bell
Friday
Solve. Check for extraneous solutions
x - 4
x
LCD Method
x - 4
x
x - 4
x
=
=
6
x - 3x
=
2
LCD:
6
x - 3x
2
6
x(x - 3)
Cross Multiplication Method
x - 4
x
=
6
x - 3x
2
(x - 4)(x2 - 3x)= 6x
x3 - 3x2 -4x2 + 12x = 6x
x3 - 7x2 + 12x = 6x
-6x -6x
x3 - 7x2 + 6x = 0
x(x2 - 7x + 6) = 0
x(x - 6)(x - 1) = 0
x = 0, x = 6, x = 1
x = 6, x = 1
HW 50
# 46
16 ­ Solving Rational Functions ­ Day 2
November 18, 2016
Solving Rational Functions - Day 2
To solve a rational equation
1. Multiply each term on both sides of the
equal sign by the LCD
• This will clear out all fractions
• Solve remaining equation
2. Check for extraneous solutions (false solutions)
• Some solutions will lead to division by zero
Example 1
Solve each equation. Check for extraneous solutions.
a.
2x
=
1
+
x + x 14
- 7
x - 7
16 ­ Solving Rational Functions ­ Day 2
b.
November 18, 2016
10
5
+ 4
=
x
x - 2
x - 2x
2
extraneous
16 ­ Solving Rational Functions ­ Day 2
c.
x2 - 4x
x2 + 2x
x2 - 9x + 20
2x2 - 9x - 5
x2 - 4x
x2 + 2x
2x2 - 9x - 5
x2 - 9x + 20
November 18, 2016
= 5
= 5
HW # 50 - Solving Rational Equations - Day 2
WS # 50
> Complete work on separate piece of paper
Unit 4 Test - Wednesday 11/24
- Be here Monday & Tuesday to review
- Quiz 1, 2, & 3 will be given back Monday