Area under Curve: Find x-intercept & y-intercept

[uradnky]

Homework Statement

Find the area bound by y= x - 2\sqrt{x} and y=0

The Attempt at a Solution

X intercept = 4
Y intercept = 0

Using verticle rectangles..

dA = ((Upper curve)-(Lower curve)) dx
\int(dA = \int(0-(x-2\sqrt{x})) dx

A= -(1/2X^2)-((2x^(3/2))/(2/3)) Evaluated from 0 to 4

A= 16

I understand this is an extremely easy question but I just cannot see where I have gone wrong with it. Is there a problem with my signs since the area I am finding is below the x-axis? Sorry if this is a bit messy, any help is appecricated, thanks.

 

[steelphantom]

You should be calculating \int2sqrt(x) - x from 0 to 4.

 

[uradnky]

That was easy. Thanks.