A formula for finding the distance between two points in the coordinate plane, derived directly from the Pythagorean theorem.
Imagine two points on a grid. Draw a horizontal line from one and a vertical line from the other to form a right triangle. The horizontal leg is the difference in x-coordinates, the vertical leg is the difference in y-coordinates, and the hypotenuseβthe direct distanceβcomes from the Pythagorean theorem. The distance formula is just a2+b2=c2 in coordinate clothing.
Showing a random 20 of 50 problems.
Example 1
medium
The equation (xβ3)2+(yβ2)2β=5 describes what?
Example 2
easy
Find the distance between (2,3) and (2,9).Find the distance between A and B (same x-coordinate).
Example 3
medium
Show that the triangle with vertices A(0,0), B(3,4), and C(6,0) is isosceles.Show triangle ABC is isosceles.
Example 4
medium
Find the points on the x-axis that are 5 units away from the point (2,4).
Example 5
easy
Find the distance between (0,0) and (3,4).Find the distance from the origin to P(3,4).
Example 6
hard
If (x,y) is equidistant from (0,0) and (6,8), find the equation relating x and y.
Example 7
easy
Find the distance between (0,0) and (9,12).Find the distance from the origin to P(9,12).
Example 8
easy
What is the distance formula between points (x1β,y1β) and (x2β,y2β)?
Example 9
hard
The midpoint of segment AB is (3,5) and A=(β1,2). Find B and the length of AB.Midpoint M=(3,5), A=(-1,2). Find B and |AB|.
Example 10
challenge
Explain why the distance formula gives the same result as the Pythagorean theorem, and what 'distance' means when the two points coincide.
Example 11
medium
A square has vertices (0,0),(a,0),(a,a),(0,a). Find the length of its diagonal in terms of a.
Example 12
medium
Find the distance in 3D between (1,2,2) and (4,6,14).
Example 13
medium
Find the distance between (1,β2) and (4,2).Find the distance between A(1,-2) and B(4,2).
Example 14
medium
Find the distance between (1,2) and (4,8), leaving the answer in simplest radical form.Find the distance in simplest radical form.
Example 15
medium
Find the distance between (β5,2) and (3,β4), in simplest radical form.Find the distance between A(-5,2) and B(3,-4).
Example 16
medium
A point (x,0) on the x-axis is equidistant from (0,0)... actually, find x so (x,0) is distance 10 from (6,8).
Example 17
medium
Show that the points A(1,1),B(4,5),C(8,2) form a right triangle.Verify triangle ABC is a right isosceles triangle.
Example 18
easy
Why does the order of subtraction not matter in the distance formula?
Example 19
easy
Find the distance between (0,0) and (5,12).Find the distance from the origin to P(5,12).
Example 20
medium
Find the distance between (2,β3) and (7,9).Find the distance between A(2,-3) and B(7,9).