SOLUTION: twice the reciprocal of a number is nine more than five times the number. find the number

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Question 98601: twice the reciprocal of a number is nine more than five times the number. find the number
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!

twice the reciprocal of a number is nine more than five times the number. 
find the number.

A number = THE number = x

The reciprocal of A number or THE number = 1%2Fx

Replace "a number" and "the number" by x:

twice the reciprocal of a number is nine more than five times the number. 

twice the reciprocal of x is nine more than five times x.

Replace "the reciprocal of x" by 1%2Fx

twice 1%2Fx is nine more than five times x.

Replace "twice 1%2Fx" by 2%2Fx.

2%2Fx is nine more than five times x.

Replace "five times x" by 5x

2%2Fx is nine more than 5x.

Replace "nine more than 5x" by 5x%2B9

2%2Fx is 5x%2B9.

Replace "is by " = "

2%2Fx = 5x%2B9.

Multiply through by x

2 = 5x%5E2%2B9x

Get 0 on the left:

0 = 5x%5E2%2B9x-2

0 = %285x-1%29%28x%2B2%29

5x-1=0, x%2B2=0
5x=1,   x=-2
x=1%2F5, x=-2

Two solutions: 1%2F5, -2

Edwin