SOLUTION: 1.find two numbers whose sum is 13 and whose product is 40
2.the area of a rectangle is 94sq. units and its perimeter is 38units.
find the length and width of the rectangle.
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-> SOLUTION: 1.find two numbers whose sum is 13 and whose product is 40
2.the area of a rectangle is 94sq. units and its perimeter is 38units.
find the length and width of the rectangle.
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Question 874981: 1.find two numbers whose sum is 13 and whose product is 40
2.the area of a rectangle is 94sq. units and its perimeter is 38units.
find the length and width of the rectangle.
You can put this solution on YOUR website! 1.find two numbers whose sum is 13 and whose product is 40
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Try pairs of factors of 40.
1*40 NG
2*20 NG
etc
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2.the area of a rectangle is 94sq. units and its perimeter is 38units.
find the length and width of the rectangle.
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P = 2L + 2W = 38
L + W = 19
L*W = 94
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L = 19 - W
Sub for L
(19-W)*W = 94
W^2 - 19W + 94 = 0
Quadratic equation (in our case ) has the following solutons:
For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
The discriminant -15 is less than zero. That means that there are no solutions among real numbers.
If you are a student of advanced school algebra and are aware about imaginary numbers, read on.
In the field of imaginary numbers, the square root of -15 is + or - .
The solution is , or
Here's your graph:
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No real number solution.
The max area of a rectangle of given perimeter is a square.
For P = 38, side length = 9.5
Area = 9.5^2 = 90.25 sq units
94 is not possible.
