Big Ideas Math Geometry, 2014
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Big Ideas Math Geometry, 2014 View details
Chapter Review
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Exercise 10 Page 57

Midpoint Coordinates: (1/2,13/2)
Distance: 5sqrt(2)≈7.1

Practice makes perfect

We are asked to calculate the midpoint of two points and the distance between them. Let's do each step separately.

Calculating the Midpoint

To find the midpoint, we can use the Midpoint Formula. (x_1+x_2/2,y_1+y_2/2)The coordinates of the given endpoints are (-2,4) and (3,9). Let's use these to find the coordinates of the midpoint.
M(x_1+x_2/2,y_1+y_2/2)
M(-2+ 3/2,4+ 9/2)
M(1/2,13/2)
The midpoint is located at ( 12, 132). We can see that on the graph.

Calculating the Distance

To determine the distance between two points we can use the Distance Formula. Recall that the coordinates of the given points are S(-2,4) and T(3,9).
ST = sqrt((x_2-x_1)^2 + (y_2-y_1)^2)
ST=sqrt(( 3-( -2))^2+( 9- 4)^2)
ST=sqrt((3+2)^2+(9-4)^2)
ST=sqrt(5^2+5^2)
ST=sqrt(25+25)
ST=sqrt(50)
Simplify right-hand side
ST=sqrt(25*2)
ST=sqrt(25)*sqrt(2)
ST=5sqrt(2)
The distance between S and T is 5sqrt(2). We can use a calculator to approximate its value. 5sqrt(2) ≈ 7.1