Can't finish equation solving step :p area between functions

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Homework Statement



The two functions are x2 and mx, where m is a positive constant. I'm asked to find the value for m where the region enclosed between the two equations in the first quadrant is equal to 8.

Homework Equations



n/a

The Attempt at a Solution



Since m is a constant, x2 and mx intersect at x = 0 and x = m. So therefore, the area between the equations would be:

(\frac{m}{2}x2 - \frac{1}{3}x3)|^{m}_{0}

Which simplifies to:

\frac{m}{2}m2 - \frac{1}{3}m3

So clearly all I need to do is set it equal to 8 and solve... however, I'm having major issues actually accomplishing this. I can't see how to get it so I just have m = (constant). Can anyone help? I know the answer I'm trying to get is ~3.63424 but no clue how to get there.
 
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m^3(1/2 - 1/3)=8
just get m^3 on one side by multiplying/dividing the equation by some appropriate number?
 
Oster said:
m^3(1/2 - 1/3)=8
just get m^3 on one side by multiplying/dividing the equation by some appropriate number?

My gosh, I didn't even notice that (m/2)(m^2) simplified to 1/2m^3. I feel so stupid now! Thank you :) I've been trying to solve it keeping the three different powers of m
 
no problem =)
 
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