Tan(theta)= pi
Now, in order for you to find the angle (theta), you would inverse tan both the left and the right to find the value. The inverse of tan is tan^-1.
tan(theta)=pi ---> theta = tan^-1(pi)
Then, you would plug tan^-1(pi) into a calculator, giving you the value
1.26
Draw an imaginary line from the vertex of angle x to the center of the circle.
This divides the 4-sided polygon into two right triangles. For example, the upper right triangle has an acute angle whose measure is 135 degrees / 2, or 67.5 degrees, and the another acute angle whose measure is x/2.
x/2 and 67.5 degrees are complementary angles, so x/2 + 67.5 deg = 90 deg. Thus, x/2 = 22.5 deg, and so x = 45 deg. (answer)
37.5% of $80 = $30
Since it is marked up, you add $30 to the current price.
$80 + $30 = $110.
Your number is 8 I believe