The formula for the area of a circle is
A=πr²
plug in the data we know
A=π4²
A=16π
Since we only we need to find the area of the shaded section, we need to twerk this equation a bit. (remember that the shaded section is 84/360 of the original circle.)
A=84/360*16π
A=11.728
A=11.73 units²
answer: A=11.73 units²
