Question

One side of an isosceles triangle whose perimeter is 42 units measures 10 units. FInd the area of the triangle.

Answer 1

from what i've read:
isoceles triangles are triangles with two congruent sides and two congruent angles.
but i can't figure what side is that 10 units
does it belong with the two congruent sides or the other side...

Answer 2

Perimeter of isosceles triangle (2*leg) + base
The measure of 10 could be a leg or a base
If 10 is a leg then both legs = 20 and the base would be 22
This cannot be a triangle because the longest side of a triangle must be less than the sum of the other 2 sides. (22 is > 20 which eliminates this from occurring.)
So the 10 length must be the base and each leg is 16.

Answer 3

then i can use A=1/2bh ?
thus obtaining the answer?

Answer 4

I'm working on the area right now

Answer 5

i got the altitude =\[\sqrt{231}\]
and the area = \[5\sqrt{231}\]
please check thanks for helping...

Answer 6

The area of a triangle = (base * height) / 2
base / 2 = 5
height² = 16² - 5²
height = sq root(231)
height = 15.1986841536
area = (15.1986841536 *5)
area = 75.9934207679

Answer 7

Looks as if we agree :-)

Answer 8

\[5\sqrt{231}= 75.99342077\]
close answer i used the formula for getting the altitude which involves that semi perimeter.. and used it for getting the area.

thanks for helping.. (gives medal) :))

Answer 9

thanks