Key Feature of Functions

On which interval is the graph decreasing?

• [-5,-3]

• [-3,-1]

• [1,4]

• [5,∞)

Answer explanation

Which point (or points) is the line sloping down when it crosses through.

How many roots does the function have?

• None

• 1

• 2

• 3

Answer explanation

Each root is caused when the graph crosses the x axis. This example crosses the axis twice.

How high was the ball when it was thrown? Choose the key feature and the answer.

• y-intercept, 0 feet

• y-intercept, 3 feet

• x-value of the vertex, 4

• y-value of the vertex 5

Answer explanation

Look for when the ball started its travel. That is the height on the y axis.

What was the maximum height of the water? Choose the key feature and the answer.

• y-intercept, 0 feet

• x-value of the vertex, 2 feet

• y-value of the vertex 10 feet

• x-intercept. 3.85 feet

Answer explanation

The max height is 10 ft on the y-axis

What key feature tells the lowest point on the roller coaster?

• y-intercept

• vertex

• Axis of Symmetry

• x-intercept

Answer explanation

WE have a lot of names for the same thing. BTW, it isn't Axis of Symmetry since that is the point of reflection for the graph, not just the vertex.

When did the ball reach its maximum height? Choose the key feature and the answer.

• y-intercept, 3 secs

• x-value of the vertex, 4 secs

• y-value of the vertex, 5 secs

• y-intercept, 0 secs

Answer explanation

Find the maximum on the graph. That is the max height also.

Find the function's x- and y-intercepts.

• x-int (0,-3) and (0,1)

  y-int (-4,0)

• x-int (-3,0) and (1,0)

  y-int (0,-4)

• x-int (-4, 1)

  y-int (-4, ∞)

• x-int (-3,0) and (1,0)

  y-int (0,-3)

Find the function's maximum and minimum points

• no maximum

  minimum (-4,-1)

• no minimum

  maximum (-3, 1)

• no maximum

  minimum (-1,-4)

• maximum (-3,1)

  minimum (0,-3)

Identify the intervals where the function is positive and where it is negative.

• positive x > -1 and negative x < -1

• positive nowhere and negative -4 < x < -1

• positive x < -3 and x > 1 and negative -3 < x < 1

• positive R and negative x < -4

Which coordinate is a relative maximum for the graph?

• None

• (0,4)

• (3,1)

• (1, -1)