answer

explanation
since there are 2 x-intercepts, the lowest degree the function could possibly have is 2, so this could be the graph of a parabola
since our zeros are at x = 4 and x = -2, our factors are (x - 4) and (x + 2)
our equation so far is
(x - 4)(x + 2)
= 
= 
since the function is reflected across the x-axis, multiply the equation by -1

= 
since the function has a vertical stretch of 3, multiply the equation by 3

= 
Answer:
Step-by-step explanation:
Approximate the integral
by dividing the region
with vertices (0,0),(4,0),(4,2) and (0,2) into eight equal squares.
Find the sum 
Since all are equal squares, so
for every 

Thus, 
Evaluating the iterate integral ![\int\limits^4_0 \int\limits^2_0 {(x+y)} \, dydx=\int\limits^4_0 {[xy+\frac{y^2}{2} ]}\limits^2_0 \, dx =\int\limits^4_0 {[2x+2]}dx\\\\=[x^2+2x]\limits^4_0=24.](https://tex.z-dn.net/?f=%5Cint%5Climits%5E4_0%20%5Cint%5Climits%5E2_0%20%7B%28x%2By%29%7D%20%5C%2C%20dydx%3D%5Cint%5Climits%5E4_0%20%7B%5Bxy%2B%5Cfrac%7By%5E2%7D%7B2%7D%20%5D%7D%5Climits%5E2_0%20%5C%2C%20dx%20%3D%5Cint%5Climits%5E4_0%20%7B%5B2x%2B2%5D%7Ddx%5C%5C%5C%5C%3D%5Bx%5E2%2B2x%5D%5Climits%5E4_0%3D24.)
Thus, 