Grade 9_Week 6_Day 1.pptx

2. Review: Find the LCD
1.
𝟏
𝟑
+
𝟏
𝟔
LCD:
2.
𝟒
𝒙
−
𝟐𝒙−𝟏
𝟓
LCD:
3.
𝟐𝒙
𝟑
+
𝒙+𝟏
𝒙
LCD:
4.
𝟏
𝒙
+
𝟐𝒙
𝟓
LCD:

3. Transforming
rational algebraic
equation to
quadratic equation

4. Quadratic Equations
Quadratic Equations are mathematical sentences of
degree 2 that can be written in the form 𝒂𝒙𝟐
+𝒃𝒙 +
𝒄 = 𝟎 where a, b, and c are real numbers and 𝑎 ≠
0
Sometimes quadratic equation are in disguise, to
get the roots of the given rational algebraic equation
transform it to the standard form of ax2+bx+c=0

5. Example:
Cross multiply
Simplify
Transpose the terms
Arrange the terms to standard form
Multiply the whole equation by -1 to
make the equation positive
3
𝑥
=
𝑥+4
7
3 7 = 𝑥 𝑥 + 4
21 = 𝑥2
+ 4𝑥
21−𝑥2
= 4𝑥
21 −𝑥2
−4𝑥 = 0
−𝑥2
− 4𝑥 + 21 = 0
(−𝑥2
−4𝑥 + 21 = 0) (−1)
𝑥2
+ 4𝑥 − 21 = 0

6. Example:
2
𝑡
−
4𝑡
2
= 7
4 − 4𝑡2
2𝑡
= 7
4 − 4𝑡2
2𝑡
=
7
1
4 − 4𝑡2
1 = 2𝑡(7)
4 − 4𝑡2
= 14𝑡
−4𝑡2
− 14𝑡 + 4 = 0
(−4𝑡2
−14𝑡 + 4 = 0) (−1)
4𝑡2
+ 14𝑥 − 4 = 0
Get the LCD of the fractions then subtract
Transpose the terms
Use 1 as the denominator of 7 and then
cross multiply
Multiply the whole equation by -1 to
make the equation positive
Transpose and then arrange to
standard form

7. S.W. Think-Pair-Share
1.
5
𝑥
=
𝑥+3
7
2.
4
𝑏
+
2𝑏
5
= 6