Quadratic Equations from Standard to Vertex

What information do you need to write an equation in vertex form? Select all that apply.

• an ordered pair anywhere on the parabola

• the coordinates for the vertex

• the formula for standard form

• the formula for vertex form

A parabola has a vertex at (-1.5,12.5) and passes through (0,8). Solve for "a" and write the equation in vertex form.

Formula: f(x) = a(x - h)² + k

• y = -1.5(12.5 - 8)²

• y = 2(x + 0)² + 8

• y = -2(x + 1.5)² + 12.5

• y = 8(x + 1.5)² - 12.5

• None of the above

Given the equation above, which of the following statements is FALSE?

• The graph opens upward.

• The vertex is at (7, 4).

• The parabola crosses the x-axis twice.

• The standard form is y= 2x² - 28x + 102.

• The axis of symmetry is x = 7.

Tags

CCSS.HSF-IF.C.7A

A parabola has a vertex at (6, 5) and passes through (10, -11). Which equation represents this parabola in vertex form?

Formula: f(x) = a(x - h)² + k

• -11 = a(10 - 6)² + 5

• y = -(10 - h)² + k

• y = -(x - 6)² + 5

• y = (x - 6)² + 5

Which answer choice(s) below correctly show(s) an equation in vertex form and in its standard form? (There may be more than 1.)

• y = -3(x + 2)² + 3

  y = -3x² - 12x - 15

• y = 2(x + 5)² + 1

  y = 2x² + 20x + 51

• y = 0.5(x - 3)² - 6

  y = 0.5x² - 3x - 1.5

Which of the following statements are TRUE? Select all that apply.

• The "a" value is positive.

• The y-intercept is positive.

• It has two zeros.

• The axis of symmetry is x = 1.

• The vertex is at (0, 5).

Tags

CCSS.HSF-IF.C.7A

Convert this equation in vertex form to standard form.

• x² -2x - 2

• x²+x-2

• x²+2

• x²-2x

Write a quadratic equation given the x intercepts and one other point.

Step 2: Find a.

Now that you know that the factors are (x-6) and (x-8), you must find a. Plug the coordinates of the vertex (7, 1) in for x and y and solve for a.

y = a(x-6)(x-8)

What is the value of a?

• a = 1

• a = -1

• a = 7

• a = -7

Which parabola would open down?

• f(x)=x²

• f(x)=-x²+3x-6

• f(x) = x²-16

• f(x)=2x²-5x+7

Tags

CCSS.HSF-IF.C.7A

Use any method (graph, factor, complete the square, quadratic formula) to solve the function:

f(x)=x²-7x+10

• No solutions

• x=-2 and x=-5

• x=2 and x=5

• x = 2/5

Tags

CCSS.HSA-REI.B.4B