Question 75139
Since the area is:
{{{A=L*w}}} we can solve for w
{{{w=A/L}}}
Now lets plug in our values
{{{w=(3x^2+5x)/x}}} plug in {{{A=3x^2+5x}}} and L=x
{{{w=3x^2/x+5x/x}}}Break up the fraction into two fractions
{{{w=3x^(cross(2))/cross(x)+5*cross(x/x)}}} Divide like terms.
{{{w=3x+5}}}
So the width is {{{w=3x+5}}}
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Check:
If we multiply L and w we should get A
{{{A=L*w}}}
{{{A=x(3x+5)}}}Plug in values for w and L
{{{A=3x^2+5x)}}} So our answer works