SOLUTION: please help me solve this math. Find the area and perimeter of a triangle whose vertices are at the points (3,4), (3,12) and (9,8). Enter your final answer as a decimal approxim

Algebra ->  Coordinate-system -> SOLUTION: please help me solve this math. Find the area and perimeter of a triangle whose vertices are at the points (3,4), (3,12) and (9,8). Enter your final answer as a decimal approxim      Log On


   

Question 926159: please help me solve this math.
Find the area and perimeter of a triangle whose vertices are at the points (3,4), (3,12) and (9,8). Enter your final answer as a decimal approximation with at least 2 decimal places. Avoid rounding as much as possible until the very end of your calculation. Don't worry about units.
TIP: Start by drawing a careful graph of the situation described. A picture will help you to think about how to approach this question.
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
The first two points indicate a side of length 8 units, and this segment is vertical. The distance from this segment to the other point is 9-3=6.

The 8 unit length can be used as a base, and the 6 unit distance (which is NOT a length of the triangle) is treated as a height; and you use formula for area of a triangle, %281%2F2%29BASE%2AHEIGHT=%281%2F2%298%2A6.


24 square units


PERIMETER

Use the distance formula for the slanted sides because you already know the vertical side length.

Perimeter is 8%2Bsqrt%28%289-3%29%5E2%2B%288-4%29%5E2%29%2Bsqrt%28%289-3%29%5E2%2B%288-12%29%5E2%29.