Posted by Amy on Wednesday, December 8, 2010 at 11:15pm.
Can anyone help with the following problem please...Thank u so much
Let f(x) =9x. For the area above the xaxis and between the lines x= 9 and x=18
a. draw and label a sketch with
the area shaded
b. find the area of the region in
the xyplane under the graph
of f(x)

PreCalc  MathMate, Wednesday, December 8, 2010 at 11:36pm
For this kind of problem, it is always desirable to make a sketch within the limits of the domain, from x=9 to 18.
See:
http://img510.imageshack.us/img510/2928/1291868155.png
Using the formula for the area of a triangle as:
Area = (1/2)base*height
You can find the areas of the two triangles between the function and the xaxis.
If you need further help, don't hesitate to post.

PreCalc  Reiny, Thursday, December 9, 2010 at 12:19am
Amy, please check to see if your question has been answered before posting the same question again.
you asked the same question with only a small change yesterday,
http://www.jiskha.com/display.cgi?id=1291781963
MathMate has gone to some length to answer it again, even creating a picture for you.
make a note of your post by jotting down the time of the first posting, even though it moves off the page, it is then rather easy to find

PreCalc  Amy, Thursday, December 9, 2010 at 12:30am
Thank you for your help
Answer This Question
Related Questions
 Precalc  Can someone please show me the steps to this problem...Thanks in ...
 PreCalc  Seeking step by step help with this question...Thank you much. Let f(...
 PreCalc  Find the area of the region between the graph of y=1/x, the xaxis, ...
 ap statistics  In a survey, 600 mothers and fathers were asked about the ...
 Math (Statistics)  (Find Normal Proportions) The lengths of Atlantic croaker ...
 brief calc  Calculate the total area of the region described. Do not count area...
 math geometry  I will try and explain this since I can't draw the picture ...
 brief calc  Calculate the total area of the region described. Do not count area...
 calculus(Lab)  Well, first graph the graph of f(x)=1/10x^2 + 3 2. We are going...
 Calc.  Find the area of the region bounded by the parabola y=x^2, the tangent ...
More Related Questions