SOLUTION: if Area=5000 Length= 30+Width then what is Width

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Question 571712: if Area=5000
Length= 30+Width
then what is Width
Answer by KMST(5347) About Me  (Show Source):
You can put this solution on YOUR website!
So as not to repeat the whole words "length" and "width" too many times, we abbreviate by saying
Let L be the length, and let W be the width.
L=W%2B30
Area=L%2AW --> Area=%28W%2B30%29W
We get the equation
%28W%2B30%29W=5000 --> W%5E2%2B30W=5000 --> W%5E2%2B30W-5000=0
We can find the solutions to that equation, applying the quadratic formula, as

We need to discard the negative solution, because the width is a positive number, and we are left with highlight%28W=-15+%2B+5sqrt%28209%29%29
L=-15+%2B+5sqrt%28209%29%2B30 --> highlight%28L=15+%2B+5sqrt%28209%29%29
Those values are not pretty, but are exact solutions. They cannot be written as exact decimals, but W = approximately 57.284 and L = approximately 87.284