Angles a, b and c are the angles in a triangle. angle b is 4 times as big as angle a and angle c is 36 degrees more than angle a. find the measure of angle a in degrees

What is the area of triangle abc if a = 8, b = 11, and c = 15?

Reflect the point (7,0) across the y-axis

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?