Solving Quadratic equations by Factoring

Solving Quadratic Equations by Factoring

For every problem, follow these steps. Write them down!!!

• 1. Make sure the equation is equal to zero.

• 2. Factor the left side of the equation (using one of these methods we learned in the last unit: trinomials where a=1, GCF, difference of squares, or trinomials where a>1). This one is a trinomial where a=1, so we just needed to find what multiplied to -8 and added to -2.

• 3. Set each factor equal to zero and solve for x. (This is what you practiced yesterday!)

Let's See Another:

So from before:

Multiple Choice

Solve the equation using the zero product property.

3x(2x - 4) = 0

• x = -1/3 or x = -2

• x = 0 or x = 2

• x = 0 or x = -2

• x = -1/3 or x = 2

Multiple Choice

Factor 6x²-27x

• (6x+1)(x+3)

• 3x(2x-9)

• 6x(x-9)

• (3x-9)(2x+3)

Multiple Choice

Solve: x² - 81 = 0

• 9

• 9, -9

• 3, -3, 9, -9

• None of the above

Multiple Choice

Solve

16a² - 9 = 0

• a = ^-3/₄, ³/₄

• a = ^-4/₃, ⁴/₃

• a = ^-9/₁₆, ⁹/₁₆

• a = ^-16/₉, ¹⁶/₉

Multiple Choice

Find the zeros of this quadratic.

• b=4/5, b=3

• b=4, b=-3

• b=1/5, b=3

• b=4/5, b=-3

Multiple Choice

Solve

x² + 9x + 20 = 0

• x = -2, x = -10

• x = -3, x = -4

• x = -4, x = -5

• x = -4, x = -6

Multiple Choice

Solve. 7m² - 12m + 5 = 0

• x = 5/7 and x = 1

• x = 8/3 and x = 2

• x = 8/3 and x = -1/2

• x = -2/3 and x = -5

Multiple Choice

Solve 2x² - 7x + 6 = 0 by factoring

• x = -3/2 and x = -2

• x = -3 and x = -2

• x = 3 and x = 2

• x = 3/2 and x = 2

Multiple Choice

Solve by factoring: x² - 9x + 20 = 0

• x = -4 and x = -5
• x = 20 and x = -9
• x = 4 and x = 5
• x = -4 and x = 5

Multiple Choice

Solve

16a² - 9 = 0

• a = ^-3/₄, ³/₄

• a = ^-4/₃, ⁴/₃

• a = ^-9/₁₆, ⁹/₁₆

• a = ^-16/₉, ¹⁶/₉

Multiple Choice

Solve by factoring: 2x²+ 7x + 6 = 0

• x= 3/2 and x = 2

• x = -3/2 and x = -2

• x = 6 and x = 7

• x = -6 and x = -7