πΊ What is 6.NS.C.8?
The Big Idea β navigating all four quadrants and measuring distance
π Standard
Solve real-world and mathematical problems by
graphing points in all four quadrants of the
coordinate plane. Use coordinates and
absolute value to find distances between points
with the same first or second coordinate.
Distance = |xβ β xβ| (same y) or |yβ β yβ| (same x)
π The coordinate plane has 4 quadrants, an
x-axis, a y-axis, and an origin (0,0). Every point is an ordered
pair (x, y).
π Distance rule: Points on the same vertical
line β subtract y-values. Points on the same horizontal line β
subtract x-values. Always take absolute value!
β οΈ 6.NS.C.8 only requires distance for points sharing an x or y
coordinate (horizontal/vertical lines). No diagonal distance
(Pythagorean theorem is Grade 8).
π QUADRANT MAP
| Quadrant | Signs | Example |
|---|---|---|
| I (upper right) | (+, +) | (3, 4) |
| II (upper left) | (β, +) | (β3, 4) |
| III (lower left) | (β, β) | (β3, β4) |
| IV (lower right) | (+, β) | (3, β4) |
π Distance via Absolute Value β The Core Idea
Why absolute value? Because distance is always positive β direction
doesn't matter.
Same x-coordinate β Vertical Distance
Points A(β3, 4) and B(β3, β2) share x = β3. They're on the
same vertical line.
d = |4 β (β2)| = |4 + 2| = |6| = 6
Same y-coordinate β Horizontal Distance
Points C(2, 5) and D(7, 5) share y = 5. They're on the same
horizontal line.
d = |2 β 7| = |β5| = 5
βοΈ TWR Frame β Describe the Distance (EN/ES)
Points
and
share the same
-coordinate, so I subtract their
values: |
β | =
units.
πͺπΈ Los puntos ___ y ___ comparten la misma coordenada ___. La
distancia es |___ β ___| = ___ unidades.
π Key Vocabulary
Academic language for 6.NS.C.8 β with Spanish cognates
Coordinate Plane
koh-OR-din-it playn
A flat surface formed by two perpendicular number lines (x-axis
and y-axis) that intersect at the origin.
Has 4 quadrants, infinite points
πͺπΈ plano de coordenadas
Ordered Pair
OR-derd pair
Two numbers (x, y) that identify a point's location β x first
(horizontal), then y (vertical).
(-3, 4) β left 3, up 4
πͺπΈ par ordenado
Quadrant
KWOD-rent
One of the four regions of the coordinate plane created by the x
and y axes. Numbered IβIV counterclockwise.
QI: (+,+) QII: (β,+)
πͺπΈ cuadrante (cognate!)
Absolute Value
AB-suh-loot VAL-yoo
The distance from zero on a number line. Always non-negative.
Written |n|.
|β6| = 6, |6| = 6, |0| = 0
πͺπΈ valor absoluto (cognate!)
Origin
OR-ih-jin
The center point (0, 0) where the x and y axes intersect on the
coordinate plane.
Every axis starts here
πͺπΈ origen (cognate!)
x-axis / y-axis
eks AK-sis
x-axis = horizontal number line. y-axis = vertical number line.
Both pass through the origin.
x: left/right Β· y: up/down
πͺπΈ eje x / eje y
π§ Morphology: "Coordinate" from Latin
coordinare = "arrange in order." "Quadrant" from
Latin quadrans = "one quarter." "Absolute" from
Latin absolutus = "set free" (from sign/direction).
π‘ Cognate Alert for ELLs:
coordinate / coordenada, quadrant / cuadrante, absolute /
absoluto, origin / origen, axis / eje
β many math terms share roots in Spanish and English!
πͺ How to Find Distance β Step by Step
Two methods: same x-coordinate (vertical) and same y-coordinate
(horizontal)
1
Identify the two points
Write both ordered pairs clearly. Label them Point A and Point
B.
A(β3, 4) and B(β3, β2)
2
Check: do they share an x-coord or y-coord?
Same x-value β vertical distance (subtract y's). Same y-value
β horizontal distance (subtract x's).
Both have x = β3 β vertical β subtract y-values
3
Subtract the coordinates that differ
Take one value minus the other. It doesn't matter which order
β absolute value fixes it.
4 β (β2) = 4 + 2 = 6
4
Apply absolute value
Distance is always positive β wrap the result in | |. This
handles cases where you subtract in the "wrong" order.
|4 β (β2)| = |6| = 6 β
5
Label your answer with units
State the distance with units: "6 units." In real-world
problems, use the actual unit (miles, feet, blocks).
Distance = 6 units
π Three Worked Examples
Vertical distance Β· Horizontal distance Β· Real-world context
π VERTICAL DISTANCE (same x)
Find the distance between P(2, 7) and Q(2, β3).
β
Same x-coordinate (x = 2) β vertical β subtract y-values
β
|7 β (β3)| = |7 + 3| = |10| = 10
β
Check: P is at y = 7 (above) and Q at y = β3 (below) β 7 units
up + 3 units down = 10 β
Distance = 10 units
π HORIZONTAL DISTANCE (same y)
Find the distance between M(β5, 3) and N(2, 3).
β
Same y-coordinate (y = 3) β horizontal β subtract x-values
β
|β5 β 2| = |β7| = 7
β
Or: |2 β (β5)| = |7| = 7 β same result!
Distance = 7 units
ποΈ REAL-WORLD (city grid)
On a city map, a library is at (β4, 2) and a park is at (3, 2).
One unit = 1 block. How many blocks apart?
β
Same y-coordinate (y = 2) β horizontal distance
β
|β4 β 3| = |β7| = 7
7 blocks apart
βοΈ TWR β Distance Explanation Frame
Points
and
share the same
-coordinate (), so I found the
distance. I subtracted: |
β | =
units.
π― Interactive Coordinate Grid
Click to place points β practice plotting all four quadrants
Click the grid to plot a point
Plot two points with the same x or y coordinate to calculate
distance automatically.
πΊ
Score
0 / 7
Progress
βοΈ Practice Problems
Type your answer Β· Click Check Β· Hints available
Problem 1
Plot
Point A is at (β3, 4) and Point B is at (β3, β2). Both share x =
β3. What is the distance between them?
units
Same x-coordinate β subtract y-values. |4 β (β2)| = ?
Problem 2
Distance
Find the distance between M(β5, 3) and N(2, 3).
units
Same y-coordinate (y=3) β subtract x-values. |β5 β 2| = ?
Problem 3
Distance
Find the distance between P(0, 6) and Q(0, β4).
units
Same x-coordinate (x=0 β on the y-axis!) β |6 β (β4)| = ?
Problem 4
Real World
A soccer field on a coordinate grid has two corners at (β6, β2)
and (6, β2). Each unit = 1 yard. How long is that side of the
field?
yards
Same y-coordinate (y=β2) β |β6 β 6| = ? yards
Problem 5
Distance
Find the distance between R(4, β5) and S(4, 8).
units
Same x-coordinate (x=4) β |β5 β 8| = ? (remember: |β13| = 13)
Problem 6
Real World
A rectangle has two vertices at (β4, 3) and (5, 3), and two more
at (β4, β2) and (5, β2). What is the perimeter of the rectangle?
units
Width: |(β4) β 5| = 9. Height: |3 β (β2)| = 5. Perimeter = 2Γ9 +
2Γ5 = ?
Problem 7
Extend
Point J is at (β7, y) and Point K is at (β7, 4). The distance
between them is 9 units. If J is below K, what is the y-coordinate
of Point J?
y-value
|4 β y| = 9. If J is below K, y is less than 4. So 4 β y = 9 β y =
4 β 9 = ?
ποΈ City Map Challenge
Solve real-world distance problems on a coordinate city grid. Each
unit = 1 city block.
πΊ The City Grid
Positive x β East Β· Negative x β West Β· Positive y β North Β·
Negative y β South
Origin (0,0) = City Hall
Origin (0,0) = City Hall
π« Question 1: The school is at (β4, 2) and the
library is at (3, 2). How many blocks is the walk from school to
library?
blocks
π₯ Question 2: The hospital is at (5, β3) and the
fire station is at (5, 6). How many blocks apart are they?
blocks
πͺ Question 3: Store A is at (β6, β1) and Store B
is at (2, β1). A delivery truck drives from Store A to Store B.
How far does it travel?
blocks
ποΈ Question 4 (Challenge): A park has corners at
(β3, 4), (β3, β2), (4, 4), and (4, β2). What is the perimeter of
the park in blocks?
blocks
βοΈ TWR β Real-World Distance Frame
The
and
are both at
,
so I found the horizontal distance. |
β | =
blocks.
π Flash Review Cards
Tap to reveal the distance. Use the formula: |coordβ β coordβ|
(2, 4) and (2, β3)
Same x β tap β©
7 units
|4β(β3)| = 7
(β5, 1) and (4, 1)
Same y β tap β©
9 units
|β5β4| = 9
(0, β6) and (0, 5)
Same x β tap β©
11 units
|β6β5| = 11
(β8, 3) and (1, 3)
Same y β tap β©
9 units
|β8β1| = 9
(6, 7) and (6, β4)
Same x β tap β©
11 units
|7β(β4)| = 11
(β3, β5) and (9, β5)
Same y β tap β©
12 units
|β3β9| = 12
(β2, 8) and (β2, β7)
Same x β tap β©
15 units
|8β(β7)| = 15
(β4, 0) and (6, 0)
On x-axis β tap β©
10 units
|β4β6| = 10
β οΈ Common Mistakes β Watch Out!
Real student errors and corrections
β
Mistake #1 β Reversing x and y when plotting
Error: Plotting (3, β4) by going down 3 and
right 4 instead of right 3 and down 4.
Fix: Ordered pair is always (x, y) β x is horizontal (left/right) FIRST, then y is vertical (up/down).
Fix: Ordered pair is always (x, y) β x is horizontal (left/right) FIRST, then y is vertical (up/down).
β
Mistake #2 β Subtracting the wrong pair
Error: For same x-coordinate, student subtracts
x-values instead of y-values.
Fix: Same x β they're on a vertical line β subtract the values that DIFFER (the y-values).
Fix: Same x β they're on a vertical line β subtract the values that DIFFER (the y-values).
β
Mistake #3 β Forgetting to use absolute value
Error: Getting a negative distance. e.g., β5 β
2 = β7, then writing "distance = β7 units."
Fix: Distance is always positive. |β7| = 7. Always take the absolute value after subtracting.
Fix: Distance is always positive. |β7| = 7. Always take the absolute value after subtracting.
β
Mistake #4 β Subtracting across quadrants incorrectly with
negatives
Error: |4 β (β2)| β student computes as |4 β 2|
= 2 instead of |4 + 2| = 6.
Fix: Subtracting a negative = adding its positive. 4 β (β2) = 4 + 2 = 6.
Fix: Subtracting a negative = adding its positive. 4 β (β2) = 4 + 2 = 6.
β
Mistake #5 β Confusing quadrant numbers
Error: Thinking Quadrant I is upper left or
numbering them clockwise.
Fix: Start Q I in the upper RIGHT (+,+). Go counterclockwise: II upper left (β,+), III lower left (β,β), IV lower right (+,β).
Fix: Start Q I in the upper RIGHT (+,+). Go counterclockwise: II upper left (β,+), III lower left (β,β), IV lower right (+,β).
π― Self-Check: After finding distance β is it
positive? β Does it make sense on the grid (can you count the
squares)? β Did you subtract the coordinates that CHANGE (not the
ones that match)? β