SOLUTION: The length of a rectangular table is 0.6m more than twice its width and its area is 4.6m^2 what are the dimensions of the table

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Question 889512: The length of a rectangular table is 0.6m more than twice its width and its area is 4.6m^2 what are the dimensions of the table
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of writing several decimal expressions too early, assign variables to everything first, and solve completely in symbols.
Let A = area
Let w = width
Let L = length
Let k=0.6
L=k+2w, and A=4.6 both which come from the description.

A=wL
A=w%28k%2B2w%29
Remember, the only variable here now is w. A and k are KNOWN.
A=kw%2B2w%5E2
2w%5E2%2Bkw=A
highlight_green%282w%5E2%2Bkw-A=0%29

Not sure by looking at that which form of the general answer will be the acceptable one, but no matter---
w=%28-k%2B-+sqrt%28k%5E2-4%2A2%2A%28-A%29%29%29%2F%284%29
The PLUS form will be wanted.
highlight%28w=%28-k%2Bsqrt%28k%5E2%2B8A%29%29%2F4%29

NOW plug in the assigned values of k and A and compute or evaluate w. Use this to evaluate L.
w=%28-0.6%2Bsqrt%280.6%5E2%2B8%2A4.6%29%29%2F4
w=%28-0.6%2Bsqrt%2837.16%29%29%2F4
I'm getting about 1.37 for w.