Precalculus (10th Edition)

Published by Pearson
ISBN 10: 0-32197-907-9
ISBN 13: 978-0-32197-907-0

Chapter 1 - Graphs - 1.1 The Distance and Midpoint Formulas - 1.1 Assess Your Understanding - Page 8: 59

Answer

Right triangle

Work Step by Step

You are given the 3 points: $(2,1), (-4,1), (-4,-3)$. Calculate the distance between each point first. Distance(P1, P2) = $\sqrt {(2-(-4))^2+(1-1)^2}$ =$\sqrt {36}$ = $6$ Distance(P2, P3) = $\sqrt {(-4-(-4))^2+(1-(-3))^2}$ =$\sqrt {16}$ = $4$ Distance(P3, P1) = $\sqrt {(-4-2)^2+(-3-1)^2}$ =$\sqrt {52}$ = $2\sqrt {13}$ Since none of the sides are equal, this triangle is not isosceles. Instead, notice how the y-coordinates of P1 and P2 are both 1, and the x-coordinates of both P2 and P3 are -4, meaning this triangle is a right-angled triangle! Another solution: Calculate $P_1P_2^2+P_2P_3^2=36+16=52$ $P_3P_1^2=52$ By the converse of the Pythagorean theorem, it means the triangle is a right triangle.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.