In this Grade 8 lesson from Reveal Math, Course 3 (Module 7), students learn how to find the distance between two points on a coordinate plane by applying the Pythagorean Theorem. They practice forming a right triangle between two points, identifying the horizontal and vertical leg lengths from the coordinates, and solving for the hypotenuse using the equation a² + b² = c². The lesson also extends this skill to real-world map problems where students calculate and compare distances using a given unit scale.
Section 1
Using the Pythagorean Theorem to Find Distance
When finding the distance between two points on a coordinate plane, you can use the Pythagorean Theorem:
where is the horizontal distance, is the vertical distance, and is the straight-line distance (the hypotenuse) between the two points. To find the distance , calculate:
Section 2
Finding Diagonal Distance Using the Pythagorean Theorem
The distance between two points is the length of the line segment connecting them.
On a coordinate plane, this segment can be treated as the hypotenuse of a right triangle.
The lengths of the legs of this triangle are the horizontal and vertical distances between the points, which can be found by subtracting the coordinates.
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Section 1
Using the Pythagorean Theorem to Find Distance
When finding the distance between two points on a coordinate plane, you can use the Pythagorean Theorem:
where is the horizontal distance, is the vertical distance, and is the straight-line distance (the hypotenuse) between the two points. To find the distance , calculate:
Section 2
Finding Diagonal Distance Using the Pythagorean Theorem
The distance between two points is the length of the line segment connecting them.
On a coordinate plane, this segment can be treated as the hypotenuse of a right triangle.
The lengths of the legs of this triangle are the horizontal and vertical distances between the points, which can be found by subtracting the coordinates.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter