Reflections Coordinate Quiz Grade 8 Mathematics • Transformations
Reflections Quiz
Name:
Date:
Score: / 15
Directions: Grid lines represent 1 unit. All lines of reflection are horizontal or vertical.
Page 1 of 3
1 Axis of Reflection
Is this a reflection over the x-axis, y-axis, or neither?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y-axis
x-axis
neither
2 Line of Reflection
Where is the line of reflection located?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
x = -6
y = 1
x = 2
y = 2
3 Target Image
Which is the reflection of ABCD over the x-axis?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 A B
Pink
Green
Blue
None
4 Reflection vs. Translation
Is this a reflection over the x-axis, y-axis, or neither?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y-axis
x-axis
neither
5 Vertical Line of Reflection
Where is the line of reflection located?
x = 1
x = -1
y = 1
y = 0
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Grade 8 Mathematics • Reflections Assessment Page 1 of 3
Part II: Transformations & Analysis
Reflections Quiz
Page 2 of 3
6 Image Identification
Which image reflects purple across x = -1 ?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Teal
Yellow
Coral
None
7 Reflected Vertices
Reflect DEF over the x-axis :
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 D E F
D' = ( , ) E' = ( , )
F' = ( , )
8 Line of Reflection
PQRS reflects to P'Q'R'S'. (P(-4,1) → P'(-4,-3))
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 P Q P' Q'
a) Horizontal or vertical?
b) Write the line of reflection:
9 Point Reflection
Reflect M(-2, 4) across dashed line x = 1 :
x = 1 x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 M(-2,4)
a) Distance to line x = 1:
units
b) Coordinates of image:
M' = ( , )
10 Geometric Verification & Reasoning
Trapezoid ABCD is reflected across the red dashed line y = 1 to create A'B'C'D'.
Is A'B'C'D' a true reflection across y = 1?
Yes
No
Explain how you know using the distance of corresponding points:
y = 1 x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 A B A' B'
Grade 8 Mathematics • Reflections Assessment Page 2 of 3
Part III: Additional Practice
Reflections Quiz
Page 3 of 3
11 Line of Reflection
Where is the line of reflection located?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y = -2
y = 2
x = -2
x = 0
12 Axis of Reflection
Is this a reflection over the x-axis, y-axis, or neither?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y-axis
x-axis
neither
13 Target Image
Which image reflects the blue shape over the y-axis?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Orange
Green
Purple
None
14 Reflection vs. Translation
Is this a reflection over the x-axis, y-axis, or neither?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y-axis
x-axis
neither
15 Vertical Line of Reflection
Where is the line of reflection located?
x = -2
x = 2
y = -2
x = 0
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Grade 8 Mathematics • Reflections Assessment Page 3 of 3
Reflexiones en Coordenadas Quiz Matemáticas de 8.º Grado • Transformaciones
Prueba de Reflexiones
Nombre:
Fecha:
Puntos: / 15
Instrucciones: Cada cuadrícula representa 1 unidad. Todas las líneas de reflexión son horizontales o verticales.
Página 1 de 3
1 Eje de Reflexión
¿Es esta una reflexión sobre el eje x, el eje y, o ninguno?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
eje y
eje x
ninguno
2 Línea de Reflexión
¿Dónde se ubica la línea de reflexión?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
x = -6
y = 1
x = 2
y = 2
3 Figura Reflejada
¿Cuál es la reflexión de ABCD sobre el eje x?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 A B
Rosa
Verde
Azul
Ninguna
4 Reflexión vs. Traslación
¿Es esta una reflexión sobre el eje x, el eje y, o ninguno?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
eje y
eje x
ninguno
5 Línea Vertical de Reflexión
¿Dónde se ubica la línea de reflexión?
x = 1
x = -1
y = 1
y = 0
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Matemáticas de 8.º Grado • Evaluación de Reflexiones Página 1 de 3
Parte II: Transformaciones y Análisis
Prueba de Reflexiones
Página 2 de 3
6 Identificación de Figura
¿Cuál figura refleja la morada sobre x = -1 ?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Verde az.
Amarillo
Coral
Ninguna
7 Vértices Reflejados
Refleja DEF sobre el eje x :
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 D E F
D' = ( , ) E' = ( , )
F' = ( , )
8 Línea de Reflexión
PQRS se refleja a P'Q'R'S'. (P(-4,1) → P'(-4,-3))
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 P Q P' Q'
a) ¿Horizontal o vertical?
b) Escribe la línea de reflexión:
9 Reflexión de un Punto
Refleja M(-2, 4) sobre la línea x = 1 :
x = 1 x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 M(-2,4)
a) Distancia a línea x = 1:
unidades
b) Coordenadas de imagen:
M' = ( , )
10 Verificación y Razonamiento
El trapecio ABCD se refleja sobre la línea discontinua roja y = 1 para formar A'B'C'D'.
¿Es A'B'C'D' una verdadera reflexión sobre y = 1?
Sí
No
Explica cómo lo sabes usando la distancia de los puntos correspondientes:
y = 1 x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6 A B A' B'
Matemáticas de 8.º Grado • Evaluación de Reflexiones Página 2 de 3
Parte III: Práctica Adicional
Prueba de Reflexiones
Página 3 de 3
11 Línea de Reflexión
¿Dónde se ubica la línea de reflexión?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
y = -2
y = 2
x = -2
x = 0
12 Eje de Reflexión
¿Es esta una reflexión sobre el eje x, el eje y, o ninguno?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
eje y
eje x
ninguno
13 Figura Reflejada
¿Cuál figura refleja la figura azul sobre el eje y?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Naranja
Verde
Morado
Ninguna
14 Reflexión vs. Traslación
¿Es esta una reflexión sobre el eje x, el eje y, o ninguno?
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
eje y
eje x
ninguno
15 Línea Vertical de Reflexión
¿Dónde se ubica la línea de reflexión?
x = -2
x = 2
y = -2
x = 0
x y -6 -4 -2 2 4 6 6 4 2 -2 -4 -6
Matemáticas de 8.º Grado • Evaluación de Reflexiones Página 3 de 3
Reflections Quiz Answer Key Teacher Resource • Answer Key & Explanations
Reflections Quiz — Teacher Key
Total Points: 15 Points
1 point per question
Covers standard 8.G.A.1 & 8.G.A.3 : Reflections over horizontal and vertical lines. Page 1 of 2
1 Axis of Reflection
y-axis
Explanation: The pre-image in Q3 (-3 to -1) reflects to the image in Q4 (1 to 3). Distances from each vertex to the y-axis (x = 0) are equal (1 and 3 units). The horizontal orientation is reversed.
2 Line of Reflection
y = 1
Explanation: The upper shape has y-values from 4 to 6; the lower shape from -4 to -2. The midpoint between corresponding points is \(\frac{6 + (-4)}{2} = 1\) and \(\frac{4 + (-2)}{2} = 1\). The line is horizontal: y = 1.
3 Target Image
Pink
Explanation: Reflecting across the x-axis transforms (x, y) → (x, -y). Pre-image ABCD in Q4 has vertices at y = -5 and -6. The reflected image must be in Q1 at y = 5 and 6, keeping identical x-values [1, 4]. That matches the Pink shape.
4 Transformation Type
neither
Explanation: Both right triangles have their right angles pointing bottom-left (orientation is unchanged). A reflection across the x-axis would flip vertical orientation. Because the shape was simply slid downward, this is a translation , not a reflection.
5 Vertical Line
x = 1
Explanation: Pre-image vertical leg lies along x = 0; image vertical leg along x = 2. Midpoint is \(\frac{0 + 2}{2} = 1\). Vertices (-2, 1) and (4, 1) have midpoint \(\frac{-2 + 4}{2} = 1\). The line is vertical: x = 1.
6 Image Identification
Teal
Explanation: Purple shape vertices lie at x = 1 and x = 4. Distance to x = -1 is 2 units and 5 units to the right. Reflecting left: -1 - 2 = -3 and -1 - 5 = -6. This matches the Teal shape. Yellow is an incorrect reflection over the y-axis.
7 Reflected Coordinates
3 Points Total
D' = (-5, -2)
E' = (-2, -5)
F' = (-2, -2)
Rule for reflection across x-axis: (x, y) → (x, -y). Negate the y-values while preserving x-values.
8 Equation of Line
2 Points Total
a) Horizontal
b) Line of Reflection: y = -1
Midpoint of corresponding y-values: \(\frac{1 + (-3)}{2} = -1\). Notice S(-1, -1) and S'(-1, -1) are identical, confirming it lies on the line of reflection.
Grade 8 Mathematics • Reflections Quiz Solutions Page 1 of 2
Teacher Resource • Key (Continued)
Reflections Quiz — Questions 9 to 15
Page 2 of 2
9 Point Reflection
2 Pts
a) Distance: 3 units
b) Coordinates: M' = (4, 4)
M(-2,4) is 3 units left of x=1. Moving 3 units right from x=1 gives x = 1 + 3 = 4. The y-value is unchanged.
10 Verification
Yes
Sample Answer: Yes, because every corresponding vertex is the exact same perpendicular distance from the line y = 1 (A and A' are both 2 units away; C and C' are both 4 units away), and the vertical orientation is flipped.
11 Line of Reflection
y = -2
Explanation: Pre-image y-values lie at 0 and -1; image y-values lie at -4 and -3. Midpoints: \(\frac{0 + (-4)}{2} = -2\). The horizontal reflection line is y = -2.
12 Axis of Reflection
y-axis
Explanation: Right triangle in Q1 has x-coordinates 2 and 5. Image in Q2 has x-coordinates -2 and -5. Since (x, y) → (-x, y), the line of symmetry is the y-axis (x = 0).
13 Target Image
Orange
Explanation: Blue shape in Q1 reflected over the y-axis flips into Q2 with negated x-values: (1, 2) → (-1, 2) and (4, 2) → (-4, 2). This matches the Orange shape.
14 Transformation Type
neither
Explanation: Both triangles face the exact same direction (right angle at bottom-left). The orientation is preserved rather than reversed. This is a translation 7 units right, not a reflection.
15 Vertical Line of Reflection
x = -2
Explanation: Left shape vertical edge is at x = -3; right shape vertical edge is at x = -1. Midpoint is \(\frac{-3 + (-1)}{2} = -2\). Outer vertices (-5, 1) and (1, 1) have midpoint \(\frac{-5 + 1}{2} = -2\). The vertical line is x = -2.
Grading Scale & Diagnostic Guide 15 Total Questions
14–15 Correct (93–100%)
Advanced Mastery: Accurately identifies lines, applies algebraic coordinate rules, and distinguishes translations from reflections.
11–13 Correct (73–90%)
Proficient: Understands axis reflections and line counting; may occasionally confuse horizontal lines (y=k) with vertical lines (x=k).
≤ 10 Correct (≤ 67%)
Needs Intervention: Struggles with orientation changes vs. translations or counting perpendicular distance to the mirror line.
Grade 8 Mathematics • Reflections Quiz Solutions Page 2 of 2
