Wednesday

March 4, 2015

March 4, 2015

Posted by **p** on Saturday, January 2, 2010 at 3:51pm.

E(7,1) and F(4,6). Classify the triangle as:

a) isosceles or scalene

b) right angled or not

- geometry -
**MathMate**, Saturday, January 2, 2010 at 4:28pmAn isosceles triangle has at least two equal sides.

To check this, we find the difference between the end-points of each of the sides, and from that, we calculate the length using Pythagoras Theorem.

D-E (-1,3)-(7,1)=(-1-7,3-1)=(-8,2)

L=√(8²+2*sup2;)=√68

E-F (7,1)-(4,6)=(7-4,1-6)=(3,-5)

L=√(3²+(-5)²)=√34

F-D (4,6)-(-1,3)=(4-(-1),6-3)=(5,3)

L=√(5²+3²)=√34

Since mEF=mFD, we conclude that the triangle DEF is isosceles.

Since mEF²+mFD²=mDE², we conclude that ∠EFD is a right angle, thus the triangle is a right-triangle.

- geometry-corr -
**MathMate**, Saturday, January 2, 2010 at 4:29pmL=√(8²+2²)=√68

**Answer this Question**

**Related Questions**

math - The vertices of a triangle are listed below. H(-2,4), I(22,4), J(10,-1) ...

Math (Geometry) - The perimeter of right triangle ABC is equal to the perimeter ...

Math - Again i wrote the question wrong. 4. Classify the triangle with angles ...

Math-CHECK PLEASE - Which of the statements is ALWAYS TRUE? A-A right triangle ...

Math - Can someone please check to see if I answered these true and false ...

Math - A triangle has 2 angles that measure 60 each. Which of the following best...

Help me - 11. Name the triangles that are classified by angles. right, scalene, ...

Geometry - A right triangle must be a. isosceles b. acute c. scalene d. either ...

Geometry - Which of the following can be used to describe the triangle with the ...

Geometry - If the measures,in degrees, of the three angles of a triangle are x, ...