CPM Homework Banner

Home > GC > Chapter 5 > Lesson 5.3.5 > Problem 5-122

5-122.

Find the area and perimeter of below. Give approximate (decimal) answers, not exact answers.
Triangle A, B, C. Angle A is 45 degrees and angle C is 30 degrees. Two internal triangles are created by a line segment of 4 drawn from the upper vertex perpendicular to the base.

Separate into two separate triangles by dropping the height from vertex .
Label the new point , creating and .

Both of the triangles that have been created are special right triangles, because the height creates two right triangles: a triangle and a triangle.

The side opposite the 45º in a  triangle is the the length of the leg times .
In a  triangle, the side opposite the 30º is half the hypotenuse and the side opposite the 60º is half the hypotenuse times .

Label the point where the line segment, 4, intersects side, A, C, as D. Divide the figure into two separate triangles, A, B, D, & B, C, D.