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Big Ideas Math Geometry, 2014

BI

Big Ideas Math Geometry, 2014 View details

3. Using Midpoint and Distance Formulas

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Exercise 28 Page 25

Use the Distance Formula.

sqrt(106) or about 10.3

Practice makes perfect

To determine the distance between two points, we use the Distance Formula. The coordinates of the given points are L(7,- 1) and M(- 2,4).

LM = sqrt((x_2-x_1)^2 + (y_2-y_1)^2)

SubstitutePoints

Substitute ( 7,- 1) & ( - 2,4)

LM=sqrt(( - 2- 7)^2+( 4-( - 1))^2)

a-(- b)=a+b

LM=sqrt((- 2-7)^2+(4+1)^2)

Add and subtract terms

LM=sqrt((- 9)^2+5^2)

Calculate power

LM=sqrt(81+25)

Add terms

LM=sqrt(106)

The distance between L and M is sqrt(106). Using a calculator we can estimate that it is about 10.3.

Subchapter links

Communicate Your Answer p.19

Monitoring Progress p.20-23

Exercises p.24-26