Answer:
90
Step-by-step explanation:
9x +5y= -45
put in standard form
y= mx+b
coefficient of x is the slope, b is the y intercpept
5y= -9x -45
y= -9/5 x -45
graphing will start at -45 on the y axis
from that point go down 9 to the right 5 for the slope continue and graph minimum
2 points to draw the line
hope this helps
(a) First find the intersections of

and

:

So the area of

is given by

If you're not familiar with the error function

, then you will not be able to find an exact answer. Fortunately, I see this is a question on a calculator based exam, so you can use whatever built-in function you have on your calculator to evaluate the integral. You should get something around 0.5141.
(b) Find the intersections of the line

with

.

So the area of

is given by


which is approximately 1.546.
(c) The easiest method for finding the volume of the solid of revolution is via the disk method. Each cross-section of the solid is a circle with radius perpendicular to the x-axis, determined by the vertical distance from the curve

and the line

, or

. The area of any such circle is

times the square of its radius. Since the curve intersects the axis of revolution at

and

, the volume would be given by