Question

Find the area of the triangle : in attachment

Answer 1

i got 78 for the big triangle.. what would the area of the little triangle be?

Answer 2

Area = 1/2 x base x height. They have given you the base and the height in the diagram.

Answer 3

39?

Answer 4

base = 6, height = 6

Answer 5

Don't mind me, just do that... :P

Answer 6

then what is the 13 for??

Answer 7

if thats the case.. the area would be 18

Answer 8

You got a 45 45 90 triangle meaning two equal sides. Use the Pythagorean equation to get the hypotenuse of the dotted line triangle and then you'll have all three sides of the purple lined triangle.

Answer 9

then just find the area from there.

Answer 10

The 13 is probably there just to confuse you.
Given the kinds of responses it's generated, it seems to be working.

Answer 11

It certainly confused me for a while, anyway.

Answer 12

Take a look at this, though.
http://www.mathsisfun.com/algebra/trig-area-triangle-without-right-angle.html
\(\frac{1}{2}bh\) seems to work for any triangle where the base and height are known, regardless of angles.