Coordinate Plane — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
The point at 3 right and 5 up is written as (5, 3).
Corrected: The point at 3 right and 5 up is written as (3, 5).
The corrected sentence is: "The point at 3 right and 5 up is written as (3, 5).". The original sentence "The point at 3 right and 5 up is written as (5, 3)." contained an error that needed to be fixed.
2. Fix the sentence:
To reach point A at (4, 2), go up 4 and right 2 from the origin.
Corrected: To reach point A at (4, 2), go right 4 and up 2 from the origin.
The corrected sentence is: "To reach point A at (4, 2), go right 4 and up 2 from the origin.". The original sentence "To reach point A at (4, 2), go up 4 and right 2 from the origin." contained an error that needed to be fixed.
3. Fix the sentence:
The origin of the coordinate plane is located at (1, 1).
Corrected: The origin of the coordinate plane is located at (0, 0).
The corrected sentence is: "The origin of the coordinate plane is located at (0, 0).". The original sentence "The origin of the coordinate plane is located at (1, 1)." contained an error that needed to be fixed.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. In the ordered pair (7, 2), the x-coordinate is 7.
In an ordered pair (x, y), the first number is always the x-coordinate. For (7, 2), x = 7.
2. In the ordered pair (3, 8), the y-coordinate is 8.
In an ordered pair (x, y), the second number is always the y-coordinate. For (3, 8), y = 8.
3. A point at the origin is written as (0, 0).
The origin is the intersection of the x-axis and y-axis at (0, 0). It is the starting point for all coordinate measurements.
4. The ordered pair (6, 0) lies on the x-axis.
A point with a y-coordinate of 0 lies directly on the x-axis. The point (6, 0) is 6 units to the right of the origin, on the horizontal x-axis.
Part C: Short Answer
Answer each question in one or two complete sentences.
1. Explain the difference between the points (2, 5) and (5, 2) on a coordinate plane.
Sample answer: The point (2, 5) is 2 units right and 5 units up from the origin, while (5, 2) is 5 units right and 2 units up. Switching the numbers changes the location because the first number is always the x-coordinate and the second is the y-coordinate.
Order matters in ordered pairs. (2, 5) and (5, 2) are in different locations because x and y have different values — swapping them gives a completely different point.
2. Maya says the point 4 units right and 6 units up from the origin is (6, 4). Is she correct? Explain.
Sample answer: Maya is not correct. The correct ordered pair is (4, 6). The x-coordinate comes first and shows distance right, so 4 right means x = 4. The y-coordinate shows distance up, so 6 up means y = 6.
The x-coordinate (horizontal distance) always comes first, the y-coordinate (vertical distance) second. Moving 4 right and 6 up gives (4, 6), not (6, 4).