What is the perimeter of a triangle with corners at $(1, 5)$ $(1 ,5 )$ , $(6, 3)$ $(6 ,3 )$ , and $(4, 1)$ $(4 ,1 )$ ?

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Answer 1 · 2018-05-15T19:37:35

$13.21$ $13.21$ to 2 decimal points. (in surd form: $\sqrt{29} + 5 + 2 \sqrt{2}$ $sqrt{29}+5+2sqrt{2}$ )

There are many ways to approach this.

Let
A = $(1, 5)$ $(1,5)$
B = $(6, 3)$ $(6,3)$
C = $(4, 1)$ $(4,1)$

Use the formula:

$d = \sqrt{{(x_{1} - x_{2})}_{1}^{2} + {(y_{1} - y_{2})}_{1}^{2}}$ $d = \sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$

to work out the distance between individual points.

Use this to work out AB, AC, and BC.

Then add up the values.

What is the perimeter of a triangle with corners at (1,5)(1 ,5 ), (6,3)(6 ,3 ), and (4,1)(4 ,1 )?