Two students are using the distance formula to determine the distance between (9, 4) and (–3, 8) on a coordinate grid. Their work is shown below.
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Plus and minus signs are positive when squared.
Option (A) is correct
There difference are each squared.
"The square of a number can be found by multiplying the number by itself. The product of two negative numbers is always positive."
Given
The distance between (9, 4) and (–3, 8) on a coordinate grid
By comparing Karlin's and Abby's work, we get
9 - (-3) = - [-3 - 9]
Squaring on both sides
[tex][9 - (-3)]^{2} = [- [-3 - 9]]^{2}[/tex]
[tex][9 +3]^{2} = [- [-12]]^{2}[/tex]
[tex][12]^{2} = [12]^{2}[/tex]
4 - 8 = - [8 - 4]
Squaring on both sides
[tex][4 - 8 ]^{2} =[ - [8 - 4]]^{2}[/tex]
[tex][-4 ]^{2} =[ - 4]^{2}[/tex]
Plus and minus signs are positive when squared.
Hence, There difference are each squared.
Learn more about square of positive and negative numbers here
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