document.write( "Question 271986: Can someone please help me with this word problem:\r
\n" ); document.write( "\n" ); document.write( "The area of a rectangle with the perimeter 100 in. is given by the formula: A=50w-w^2 where w is the width. Find the value of w that produces the maximum area. \r
\n" ); document.write( "\n" ); document.write( "the only way i could try to figure this out is to make columns with the length and width dimensions that equal 100 in perimeter and plug the width into the equation. I started using the width of 45 and worked down to 30 which has the area of 600. But since a square is also a rectangle, do I use 25? Is there an easier way to figure this? Thanks
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Algebra.Com's Answer #199055 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
Yes, there is an easier way using algebra.
\n" ); document.write( "Graph the given function which that shows the area (A) as a function of the width (w). A (area) is the vertical axis while w (width) is the horizontal axis.
\n" ); document.write( "\"graph%28400%2C400%2C-5%2C60%2C-5%2C660%2C50x-x%5E2%29\"
\n" ); document.write( "You can see from the graph that this is a parabola opening downward so there is a maximum (area) at (w, A) of (25, 625).
\n" ); document.write( "You can find the w coordinate of the vertex by:
\n" ); document.write( "\"w+=+%28-b%29%2F2a\" where: b = 50 and a = -1, so...
\n" ); document.write( "\"w+=+%28-50%29%2F%282%28-1%29%29\"
\n" ); document.write( "\"w+=+25\"
\n" ); document.write( "The vertex (maximum area in this case) occurs at w = 25.
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