A rectangle with sides measuring x in. and 4x-1 in. has an area of 663in.^2. What are the dimensions of the rectangle?
1 answer:
9514 1404 393
Answer:
13 in by 51 in
Step-by-step explanation:
The area is the product of the dimensions, so is ...
663 = x(4x -1)
4x^2 -x -663 = 0 . . . . . . subtract 663 to put in standard form
Using the quadratic formula, we can find the solutions.
x = (-(-1) ±√((-1)^2 -4(4)(-663)))/(2(4))
x = (1 ± √10609)/8 = (1 ±103)/8
Only the positive solution is of any use in this problem, so ...
x = 104/8 = 13
4x-1 = 4(13)-1 = 51
The dimensions of the rectangle are 13 inches by 51 inches.
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I find it easiest to solve these using a graphing calculator.
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Answer: B. No
Step-by-step explanation:
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Where the constant of variation is "k".
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As you can observe in the table, when the value of the variable "x" increase, the values of the variable "y" decrease, therefore we can conclude that it is not a direct variation.
Then the answer is the option B.