Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Simplifying Rational Expressions
Unit 6
Section 18
Mar 28­3:32 PM
Remember: A rational number is a number that is expressed in the form
where m and n are integers and n cannot equal zero!!
Rational expression: an expression that can be written in the form
where p and q are polynomials and q = 0.
You will be asked to find the values, or restrictions, on the
variables that appear in the denominator. To do this you
must solve for all values that make the denominator zero.
Mar 28­3:32 PM
1
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Example 1: Simplify and state the restrictions on x.
(x + 3)(x + 4)
(x + 3)(x + 2)
The only common factor here is "x + 3", so cancel that off and we get:
(x + 4) (x + 2)
x + 4 4
= = 2
x + 2 2
You can only cancel factors, not terms!
Mar 28­3:33 PM
Examples: Simplify and state the restrictions.
1.)
2.)
3.)
Mar 28­3:33 PM
2
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Simplify. State all restrictions on variables. 4.)
5.)
6.)
7.)
5) 4d ­ 20
12d
6) Mar 28­3:34 PM
Mar 28­3:35 PM
3
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Homework Packet:
page 63, 64
Apr 19­10:27 AM
Bell Ringer:
-Write the equation of the line in slope intercept and
standard form that goes through (1, 6) and (2, -5).
-Write the equation of the line that is parallel to
y = 2x + 3 and goes through the point (3, 2).
Apr 30­8:25 PM
4
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Zero divided by Zero
is UNDEFINED!!
Proof:
0.1
0.1
= 1
0
0.1
0.001
0.001
= 1
0
= 0
0.001
0.0001
0.0001
= 1
0
= 0
0.0001
= 0
Therefore, you have to make the
restrictions before canceling out the
factors!
Apr 30­7:10 PM
Apr 30­7:04 PM
5
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Keystone Review- Exit Ticket:
Write the equation of the line that is
Perpendicular to y = 1 x - 4 and goes through
2
the point (2, 3).
HW: page 64, Keystone Packet
May 9­8:25 AM
Apr 30­8:26 PM
6
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Bell RingerFactor Completely and State the Restrictions:
2
4x - 12x + 9
2
x - 8x + 15
2
6x - 9x
2
x - 25
Apr 30­8:28 PM
Apr 30­8:28 PM
7
Unit 6 Section 15 Simplifying Rational Expressions.notebook
May 02, 2016
Keystone Review- Exit Ticket:
Write the equation of the line parallel to
y = -4x - 5 that goes through the
point (2, 3).
Homework: Keystone Packet
Apr 30­8:56 PM
Apr 30­10:00 PM
8