I did these problems, teacher said they were wrong and sent me away to do them again. I tried and still got the same answers.
A) Find the perimeter to the figure
B) The Enclosed area:
12002.jpg picture by EdenJonas - Photobucket
In a right angle triangle, the hypotenuse is the longest side. It is also the side opposit to the right angle. So here, the hypotenuse is the side which length is 10.
And the Pythagorean theorem says
Hence the length of the third side is not , but... ?
The perimeter is the sum of the sides that are on the outside.
This means that the perimeter of your figure is 8+10+the length of the semicircle.
You're not asked for the perimeter of the triangle !!!
Now, do you know the formula for the perimeter and the area of a circle ?
What is the radius of this semicircle ?
The perimeter of the triangle would be 8+10+6.
Not with the squares. Please read carefully the formula from the Pythagorean theorem !