Summative 4.2: Vertex Form of Quadratic Functions

Which of the following equations matches vertex form of a quadratic?

• ax + by = c
• y = a(x - h)² + k
• y = ax² + bx + c
• y = mx + b

What effects does "a" have on the parent function?

• Vertical stretch/compression

• Horizontal shifts (left/right)

• Vertical shifts (up/down)

What effects does "k" have on the parent function?

• Vertical stretch/compression
• Horizontal shifts (left/right)
• Vertical shifts (up/down)

What effects does "h" have on the parent function?

• Vertical stretch/compression
• Horizontal shifts (left/right)
• Vertical shifts (up/down)

How can you tell the direction of the opening of the graph of a parabola by looking at the equation?

• The vertex tells you the direction of the opening
• The value of "a" tells you the direction of the opening.
• All parabolas open upward
• All parabolas open downward

What causes the graph of y = x² to open downward?

• multiply the x² by a fraction
• multiply the x² by a decimal
• multiply the x² by a negative number
• multiply the x² by a number greater than 1

Which graph would be widest?

• $y=3x^2+8$

• $y=\frac{1}{3}x^2$

• $y=-5x^2+2$

• $y=x^2-6$

Which graph would be the skinnest?

•  $y=6x^2+1$ 

•  $y=\frac{4}{7}x^2\ +9$ 

•  $y=-10x^2+2$ 

•  $y=x^2+9$ 

Explain the translation:

y = x² - 7

• translated left 7

• translated right 7

• translated up 7

• translated down 7

Explain the translation:

y = (x + 14)²

• translated up 14

• translated down 14

• translated right 14

• translated left 14