7,-2,-17,-2.53 least to greatest

Find the sum of the measure of the interior angles of a polygon of 9 sides ; of 32 sides

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

Two line segments are shown in the figure below. suppose that the length of the line along the x-axis is 6, and the length of the hypotenuse of the triangle is 10. what is the equation of the hypotenuse line (shown in red, below)?