SUBW051525

What is the axis of symmetry?
f(x) = x² - 8x + 15.

• x = -4

• x = 4

• y = 4

• y = -4

Answer explanation

The axis of symmetry for a quadratic function in the form f(x) = ax^2 + bx + c is given by x = -b/(2a). Here, a = 1 and b = -8, so x = -(-8)/(2*1) = 4. Thus, the correct answer is x = 4.

Tags

CCSS.HSA.REI.B.4

What is the axis of symmetry of y=2x²-4x+9?

• x = 1

• x = -1

• x = -2

• x = 4

Answer explanation

The axis of symmetry for a quadratic equation in the form y = ax^2 + bx + c is given by x = -b/(2a). Here, a = 2 and b = -4, so x = -(-4)/(2*2) = 1. Thus, the axis of symmetry is x = 1.

Tags

CCSS.HSA.REI.B.4

Which expression results in 10?

• 50 - [ 5 + (8 x 5) ]

• (10 ÷ 2) + (10 ÷ 2)

• (70 ÷ 7) x 10

• 30 ÷ [ (20 ÷ 4) + 1 ]

Answer explanation

The expression (10 ÷ 2) + (10 ÷ 2) simplifies to 5 + 5, which equals 10. The other options do not result in 10 when calculated.

Tags

CCSS.5.OA.A.1

CCSS.5.OA.A.2

(2x + 3)(x - 4)

• 2x² - 5x - 12

• 2x² - 8x + 12

• 2x² - 5x + 12

• 2x² + 5x - 12

Answer explanation

To expand (2x + 3)(x - 4), use the distributive property: 2x*x + 2x*(-4) + 3*x + 3*(-4) = 2x^2 - 8x + 3x - 12 = 2x^2 - 5x - 12. Thus, the correct answer is 2x^2 - 5x - 12.

Tags

CCSS.HSA.APR.A.1

Find the product:
(x - 8)(x + 8)

• x² - 64

• x² + 64

• x² - 8x + 64

• x² + 8x - 64

Answer explanation

To find the product of (x - 8)(x + 8), use the difference of squares formula: a^2 - b^2. Here, a = x and b = 8. Thus, (x - 8)(x + 8) = x^2 - 8^2 = x^2 - 64. The correct answer is x^2 - 64.

Tags

CCSS.HSA.APR.A.1

• 6x² + 16x + 8

• 5x² + 11x + 6

• 5x² + 16x + 6

• 6x² + 11x + 8

Answer explanation

To find the product, use the distributive property: (3x)(2x) + (3x)(4) + (2)(2x) + (2)(4) = 6x^2 + 12x + 4x + 8 = 6x^2 + 16x + 8. Thus, the correct answer is 6x^2 + 16x + 8.

Tags

CCSS.HSA.APR.A.1

Answer explanation

To find the product, use the distributive property: (2x-7)(x+2) = 2x^2 + 4x - 7x - 14 = 2x^2 - 3x - 14. Thus, the correct answer is 2x^2 - 3x - 14.

Tags

CCSS.HSA.APR.A.1

Answer explanation

To multiply, distribute 2x across each term in the parentheses: 2x * 3x^2 = 6x^3, 2x * 4x = 8x^2, and 2x * -6 = -12x. Combining these gives 6x^3 + 8x^2 - 12x, which matches the correct answer.

Tags

CCSS.HSA.APR.A.1

Multiply (x - 2) (5x² + 3x - 1)

• 5x³ - 13x² - 7x + 2

• 5x³ - 10x² + 7x + 2

• 5x³ - 7x² - 7x + 2

• 5x³ + 13x² + 7x + 2

Answer explanation

To multiply (x - 2)(5x^2 + 3x - 1), use the distributive property: x(5x^2 + 3x - 1) - 2(5x^2 + 3x - 1). This results in 5x^3 - 10x^2 + 3x + 2, simplifying to 5x^3 - 7x^2 - 7x + 2, which matches the correct answer.

Tags

CCSS.HSA.APR.A.1

Multiply (x² - 5) (x² + 3)

• x² - 2x - 15

• x⁴ - 2x² - 15

• x² - 2x + 15

• x⁴ - x - 15

Answer explanation

To multiply (x² - 5)(x² + 3), use the distributive property: x²*x² + 3x² - 5x - 15. This simplifies to x⁴ - 2x² - 15, which matches the correct answer choice.

Tags

CCSS.HSA.APR.A.1