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x(x+3.7)= 18.3

On my assignment I've got a question that I'm stuck with.  I've got to find dimensions of a rectangle with the
information that is given:
Area: 18.3 cm;
Width: x
Length: x+3.7
so i came up with:
Then when I'm trying to use the quadratic equation formula - I come up with answers, which do not work for me. HELP!

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Richard P. | Fairfax County Tutor for HS Math and ScienceFairfax County Tutor for HS Math and Sci...
4.9 4.9 (638 lesson ratings) (638)
The quadratic formula will work for this problem.
We have a = 1
b = 3.7
c = - 18.3
We compute (-3.7 + sqrt(3.72 + 4 18.3) /2   =  2.81
We must take the positive sign of the square root, else we get a negative length (not physical).
Note also that the expression has + 4 18.3  because c is negative.
To check, we note that 2.81 (2.81 + 3.7) does equal 18.3