Solving Quadratic Equations by Factoring Lesson

Convert x² - 9x + 20 to factored form and solve.

• (x-10)(x+2); x = -2, 10
• (x+4)(x+5); x = -5, -4
• (x-4)(x-5); x = 4, 5
• Not factorable

Tags

CCSS.HSA-REI.B.4B

Factor 6x²-27x

• (6x+1)(x+3)
• 3x(2x-9)
• 6x(x-9)
• (3x-9)(2x+3)

The solutions of the quadratic equation 
x²+2x-15=0 are

• x = 3 or x = 5
• x = 5 or x = -3
• x = -5 or x = 3
• x = -3 or x = -5

Tags

CCSS.HSA-REI.B.4B

The solutions of the quadratic equation

x²+12x+35=0 are

FACTOR FIRST! (x __)(x__) = 0. THEN set each parentheses = to 0 to get solutions.

• x = -5 or x = -7

• x = 5 or x = 7

• x = -35 or x = -1

• x = -9 or x = -4

Tags

CCSS.HSA-REI.B.4B

Factor x² + 6x + 9 and solve for x. 

• (x+3)(x+3); x = -3
• (x+4)(x+5); x=-4, -5
• (x-3)(x-3); x=3
• Not factorable

Tags

CCSS.HSA-REI.B.4B

What are the solutions to this equation? (x-3)(x+2)=0

FACTOR FIRST! (x __)(x__) = 0. THEN set each parentheses = to 0 to get solutions.

• x=3,-2

• x=-3,2

• x=2,3

• x=3,2

Tags

CCSS.HSA-REI.B.4B

The solutions of the quadratic equation

x²4x+4=0 are

FACTOR FIRST! (x __)(x__) = 0. THEN set each parentheses = to 0 to get solutions.

• x = 2

• x = -2

• x = -4 or x = 1

• x = -4 or x = -1

Tags

CCSS.HSA-REI.B.4B

Solve

x² + 2x - 20 = 4

1) MAKE EQUATION = 0 on RIGHT SIDE!

2) FACTOR FIRST! (x __)(x__) = 0. THEN set each parentheses = to 0 to get solutions.

• x = -6, x = 4

• x = 6, x = -4

• x = 12, x = -2

• x = 8, x = -3

Tags

CCSS.HSA-REI.B.4B

What should you do first in solving this equation?
x² + 6x - 13 = 3

• Get factored form
• Find two numbers which add to make 6 and multiply to make -13
• Make it equal 0 by subtracting 3 on each side
• Type it all in a calculator.

Tags

CCSS.HSA-REI.B.4B

Solve by factoring:

n² - 2n = 0

*FACTOR OUT A GCF. SET BOTH FACTORS = 0 and solve for n.

• n = 2 and 0

• n = -2 and 0

• n = 2

• n = 0

Tags

CCSS.HSA-REI.B.4B