Equation of a tangent line of a curve is:
y- y0 = f´ (x0) (x - x0 ). In this case: x0=1, y0=1
f´(x)=

(Derivation)
f´(x0)=

y - 1 = 1/2 ( x - 1 )
y - 1 = 1/2 x - 1/2
y = 1/2 x - 1/2 + 1
y =
Interior angles are the angles on the interior of a shape, for example the interior angles of a square are 90(degrees)
First, you need to get delta which is b squared minus 4ac. If delta is higher than cero, the polynomial has two solutions, if it is less, the polynomial has no real solutions and if it is the same, it has one solution.
Although that is only for second grade ecuations
360 divided by x = 21.2 recurring
So rearrange that to get x = 360 divided by 21.2
Which rounds up to 17