SOLUTION: A rectangular sign must have an area of 23 square yards. its length must be 6 yards more than its width. find the dimensions of the sign?

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Question 1009425: A rectangular sign must have an area of 23 square yards. its length must be 6 yards more than its width. find the dimensions of the sign?
Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.
Solve this quadratic equation for the unknown value of the width w

w*(w+6) = 23,

which is the same as 

w%5E2+%2B+6w+-+23 = 0.

Use the quadratic formula. You will get

w%5B1%2C2%5D = %28-6+%2B-+sqrt%286%5E2+%2B4%2A23%29%29%2F2 = %28-6+%2B-+sqrt%28128%29%29%2F2 = %28-6+%2B-+8%2Asqrt%282%29%29%2F2 = -3+%2B-+4%2Asqrt%282%29.

The negative root doesn't fit the condition.

Hence, w = 4%2Asqrt%282%29+-+3 is the unique solution.