Recall that to get the x-intercepts, we set the f(x) = y = 0, thus
![\bf \stackrel{f(x)}{0}=-4cos\left(x-\frac{\pi }{2} \right)\implies 0=cos\left(x-\frac{\pi }{2} \right) \\\\\\ cos^{-1}(0)=cos^{-1}\left[ cos\left(x-\frac{\pi }{2} \right) \right]\implies cos^{-1}(0)=x-\cfrac{\pi }{2} \\\\\\ x-\cfrac{\pi }{2}= \begin{cases} \frac{\pi }{2}\\\\ \frac{3\pi }{2} \end{cases}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7Bf%28x%29%7D%7B0%7D%3D-4cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%5Cimplies%200%3Dcos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%0A%5C%5C%5C%5C%5C%5C%0Acos%5E%7B-1%7D%280%29%3Dcos%5E%7B-1%7D%5Cleft%5B%20cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%20%5Cright%5D%5Cimplies%20cos%5E%7B-1%7D%280%29%3Dx-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%0A%5C%5C%5C%5C%5C%5C%0Ax-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%3D%0A%5Cbegin%7Bcases%7D%0A%5Cfrac%7B%5Cpi%20%7D%7B2%7D%5C%5C%5C%5C%0A%5Cfrac%7B3%5Cpi%20%7D%7B2%7D%0A%5Cend%7Bcases%7D)
Answer:
Part a) The measure of the missing angle is 
Part b) The triangle of the figure is a right triangle
Part c) The triangle of the figure is a scalene triangle
Step-by-step explanation:
we know that
The sum of the interior angles of a triangle is equal to 
so
Let
x------> the missing angle
we know that

solve for x

The triangle of the figure is a right triangle --------> by its angles
Because the triangle has an angle measure of 
The triangle of the figure is a scalene triangle --------> by its sides
Because the three angles and the three sides measures are different
d) x=-12 because x/-3=4 can be rearranged as x=4x-3 so x=-12
Hi!
We can set up a proportion then cross multiply to solve this.

45 x 100 = 4500
4500/18 = 250
The answer is 250
Hope this helps! :)
Answer:
Average rate of change = 2
Step-by-step explanation:
Find the average rate of change for f(x) = x^2 − 3x − 10 from x = −5 to x = 10.
f(-5) = (-5)^2 − 3(-5) − 10 = 25 + 15 - 10 = 30
f(10) = 10^2 − 3(10) − 10 = 100 - 30 - 10 = 60
Average rate of change:
f(10) - f(-5) 60 - 30 30
-------------------- = ------------------------------- = ----------------------- = 2
10 - (-5) 15 15