2-5: MIDPOINTS

2-5: MidpointsTHEOREM 2-5: Midpoint Formula for a Number Line

On a number line, the coordinates of the midpoint of a segment whose endpoints have the coordinates a and b is

2-5: MidpointsTHEOREM 2-6: Midpoint Formula for a Coordinate Plane

On a coordinate plane, the coordinates of the midpoint of a segment whose endpoints have the coordinates (x1, y1) and (x2, y2) are

2-5: MidpointsUse the number line below to find the coordinates of the midpoint to:

RS

RT

2-5: MidpointsFind the coordinates of M, the midpoint of JK, given endpoints J(2, -9) and K(8, 3)

Find the coordinates of N, the midpoint of VW, given endpoints V(-4, -3) and W(6, 11)

2-5: MidpointsSometimes, instead of being asked to find the midpoint given the two endpoints, you may be asked to find one of the endpoints given the other endpoint and the midpoint.ExampleSuppose G(8, -9) is the midpoint of FE and the coordinates of E are (18, -21). Find the coordinates of F.Solution: Solve the x and y coordinates separately (on next slide)

2-5: MidpointsExampleSuppose G(8, -9) is the midpoint of FE and the coordinates of E are (18, -21). Find the coordinates of F.x-coordinatey-coordinate

F is at (-2, 3)

2-5: MidpointsYour TurnSuppose K(-10, 17) is the midpoint of IJ and the coordinates of J are (4, 12). Find the coordinates of I. F is at (-24, 22)

2-5: MidpointsAssignmentWorksheet #2-5