You can use the Theorem of Pythagoras to calculate the length of the sides: between (3,1) and (7,2) x has a difference of 7-3=4 and y 2-1=1 So a Line which connects them would be a=√4^2+1^2=√8+1=√9=3 If you Want the Line between (-1,2) and (3,1) you do it the Same way: ∆x=3-(-1)=3+1=4 and ∆y=1-2=-1 in This case, you can forget about the - because we are looking for the difference. b=√4^2+1^2=√9=3 So the Same with the Last Line
A triangle has vertices (-1, 2), (3, 1), and (7, 2). What is the approximate perimeter of the triangle? Round your answer to the nearest hundredth.