Let's analyze each quadratic graph one by one and identify the key features:
x-intercepts, y-intercept, vertex, point of extremum (maximum or minimum), axis of symmetry, roots, solutions, and zeros.
---
🔷 Graph 1
#### Graph Description:
- Parabola opens
downward (so it has a
maximum).
- Vertex at
(1, 4).
- Crosses x-axis at
x = -1 and
x = 3.
- Crosses y-axis at
y = 3.
- Axis of symmetry is halfway between the x-intercepts: $ x = \frac{-1 + 3}{2} = 1 $.
####
✔ Key Features:
-
X-Intercept(s): $ x = -1 $ and $ x = 3 $
-
Y-Intercept: $ y = 3 $
-
Vertex: $ (1, 4) $
-
Point of Extremum: Maximum, $ y = 4 $
-
Axis of Symmetry: $ x = 1 $
-
Root(s): $ x = -1 $, $ x = 3 $
-
Solution(s): $ x = -1 $, $ x = 3 $
-
Zero(s): $ x = -1 $, $ x = 3 $
> Note: Roots, Solutions, and Zeros are all the same in this context — they refer to the x-values where the function equals zero.
---
🔷 Graph 2
#### Graph Description:
- Parabola opens
downward →
maximum.
- Vertex at
(-1, 2).
- Crosses x-axis at
x = -3 and
x = 1.
- Crosses y-axis at
y = -4.
- Axis of symmetry: midpoint of $-3$ and $1$: $ x = \frac{-3+1}{2} = -1 $
####
✔ Key Features:
-
X-Intercept(s): $ x = -3 $, $ x = 1 $
-
Y-Intercept: $ y = -4 $
-
Vertex: $ (-1, 2) $
-
Point of Extremum: Maximum, $ y = 2 $
-
Axis of Symmetry: $ x = -1 $
-
Root(s): $ x = -3 $, $ x = 1 $
-
Solution(s): $ x = -3 $, $ x = 1 $
-
Zero(s): $ x = -3 $, $ x = 1 $
---
🔷 Graph 3
#### Graph Description:
- Parabola opens
downward →
maximum.
- Vertex at
(-2, 4).
- Crosses x-axis at
x = -4 and
x = 0.
- Crosses y-axis at
y = 0 (since it passes through origin).
- Axis of symmetry: $ x = \frac{-4 + 0}{2} = -2 $
####
✔ Key Features:
-
X-Intercept(s): $ x = -4 $, $ x = 0 $
-
Y-Intercept: $ y = 0 $
-
Vertex: $ (-2, 4) $
-
Point of Extremum: Maximum, $ y = 4 $
-
Axis of Symmetry: $ x = -2 $
-
Root(s): $ x = -4 $, $ x = 0 $
-
Solution(s): $ x = -4 $, $ x = 0 $
-
Zero(s): $ x = -4 $, $ x = 0 $
---
✔ Final Answer Summary
####
Graph 1
- X-Intercept(s): $ x = -1, 3 $
- Y-Intercept: $ y = 3 $
- Vertex: $ (1, 4) $
- Point of Extremum:
Maximum, $ y = 4 $
- Axis of Symmetry: $ x = 1 $
- Root(s): $ x = -1, 3 $
- Solution(s): $ x = -1, 3 $
- Zero(s): $ x = -1, 3 $
####
Graph 2
- X-Intercept(s): $ x = -3, 1 $
- Y-Intercept: $ y = -4 $
- Vertex: $ (-1, 2) $
- Point of Extremum:
Maximum, $ y = 2 $
- Axis of Symmetry: $ x = -1 $
- Root(s): $ x = -3, 1 $
- Solution(s): $ x = -3, 1 $
- Zero(s): $ x = -3, 1 $
####
Graph 3
- X-Intercept(s): $ x = -4, 0 $
- Y-Intercept: $ y = 0 $
- Vertex: $ (-2, 4) $
- Point of Extremum:
Maximum, $ y = 4 $
- Axis of Symmetry: $ x = -2 $
- Root(s): $ x = -4, 0 $
- Solution(s): $ x = -4, 0 $
- Zero(s): $ x = -4, 0 $
---
📝 Notes:
- All three parabolas open
downward, so they have
maximums.
- The
vertex is always the highest point.
-
Axis of symmetry is the vertical line through the vertex.
-
X-intercepts,
roots,
solutions, and
zeros are all synonymous here — they are the values of $ x $ where $ y = 0 $.
-
Y-intercept is where $ x = 0 $.
Let me know if you'd like the equations of the quadratics as well!
Parent Tip: Review the logic above to help your child master the concept of characteristics of quadratic functions worksheet answers.