Factoring Quadratic Equations

• (x+2)(x+4)

• (x-2)(x-4)

• (x-8)(x-1)

• (x+1)(x+8)

Answer explanation

To factorise x^2-9x+8=0, we need to find two numbers that multiply to 8 and add up to -9. The numbers are -8 and -1, so the factors are (x-8)(x-1).

Tags

CCSS.HSA-REI.B.4B

• (x-7)(x+2)

• (x+7)(x-2)

• (x+7)(x+2)

• (x-7)(x-2)

Answer explanation

To find the factors, rearrange the equation to get x^2 - 5x - 14 = 0. Then factor the quadratic to get (x-7)(x+2), so the correct choice is (x-7)(x+2).

Tags

CCSS.HSA-REI.B.4B

• (x+9)(x-2) = 0

• (x-9)(x-2) = 0

• (x+9)(x+2) = 0

• (x-9)(x+2) = 0

Answer explanation

To factorise x^2-7x-18, we need to find two numbers that multiply to -18 and add up to -7. The numbers are -9 and 2, so the correct factorization is (x-9)(x+2).

Tags

CCSS.HSA-REI.B.4B

• 7x(9x) = 0

• 7x(x+9) = 0

• x(7x+9) = 0

• 7(x+9) = 0

Answer explanation

To factorise 7x^2+9x with GCF, we find the common factor which is x. Then we divide each term by x to get x(7x+9), which is the correct factorisation.

Tags

CCSS.HSA-REI.B.4B

• (x+5)(x+5)

• (x-5)(x-5)

• (x+5)(x-5)

• (x-15)(x+5)

Answer explanation

(x+5)(x-5) is the correct factorization of x^2-25=0 by applying the difference of squares formula, where a^2 - b^2 = (a+b)(a-b). In this case, a=x and b=5.

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.

Answer explanation

Make it equal 0 by subtracting 3 on each side

Tags

CCSS.HSA-REI.B.4B

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

Answer explanation

To solve the equation, factor 2x^2 + 7x + 6 = 0 into (2x + 3)(x + 2) = 0. Set each factor to zero to find x = -3/2 and x = -2 as the correct answers.

Tags

CCSS.HSA-REI.B.4B

Solve by factoring: 3x² + 5x + 2 = 0  

• x = -2/3 and x = -1

• x = -3/2 and x = -1

• x = 2/3 and x = 1

• x = 2/3 and x = -1

Answer explanation

To solve the equation 3x^2 + 5x + 2 = 0 by factoring, we find two numbers that multiply to 6 and add up to 5. These numbers are 2 and 3. Therefore, the solutions are x = -2/3 and x = -1.

Tags

CCSS.HSA-REI.B.4B

Solve by factoring:  4x² + 11x - 3 = 0

• x = -3/4 and x = -1

• x = 4 and x = 3

• x = 1/4 and x = -3

• x = -1/4 and x = 3

Answer explanation

To solve the equation by factoring, find two numbers that multiply to -12 (product of 4*-3) and add up to 11. The numbers are 12 and -1. Therefore, the solutions are x = 1/4 and x = -3.

Tags

CCSS.HSA-REI.B.4B

Solve by factoring: 5x² + 13x + 6 = 0

• x = -2 and x = -3/5

• x = 2 and x = 3/5

• x = -2 and x = 3/5

• x = 2 and x = -3/5

Answer explanation

To solve the quadratic equation 5x^2 + 13x + 6 = 0, we need to factor it as (5x + 2)(x + 3) = 0. Setting each factor to zero gives x = -2 and x = -3/5.

Tags

CCSS.HSA-REI.B.4B