Answer:
<em><u>=</u></em><em><u> </u></em><em><u>7</u></em><em><u> </u></em><em><u>.</u></em>
From the working above
Answer:
- x = ±√3, and they are actual solutions
- x = 3, but it is an extraneous solution
Step-by-step explanation:
The method often recommended for solving an equation of this sort is to multiply by the product of the denominators, then solve the resulting polynomial equation. When you do that, you get ...
... x^2(6x -18) = (2x -6)(9)
... 6x^2(x -3) -18(x -3) = 0
...6(x -3)(x^2 -3) = 0
... x = 3, x = ±√3
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Alternatively, you can subtract the right side of the equation and collect terms to get ...
... x^2/(2(x -3)) - 9/(6(x -3)) = 0
... (1/2)(x^2 -3)/(x -3) = 0
Here, the solution will be values of x that make the numerator zero:
... x = ±√3
_____
So, the actual solutions are x = ±3, and x = 3 is an extraneous solution. The value x=3 is actually excluded from the domain of the original equation, because the equation is undefined at that point.
_____
<em>Comment on the graph</em>
For the graph, we have rewritten the equation so it is of the form f(x)=0. The graphing program is able to highlight zero crossings, so this is a convenient form. When the equation is multiplied as described above, the resulting cubic has an extra zero-crossing at x=3 (blue curve). This is the extraneous solution.
Answer:
1.50
Step-by-step explanation:
8 x 1.50=12
25-12=13
13-4=9
9/6=1.5
Answer:
2 mm
Step-by-step explanation:
Let x be the sides of the original square,
then the area of the original square is x^2
The sides of the new square is x + 6
The area is (x + 6)^2
Then (x + 6)^2 = 16*x^2
Take square root on both sides and get
x + 6 = 4x,
3x = 6
so x = 2 mm
The speed of the car per minute is 3,520 feet (choice c). This is because in order to solve the problem, you have to convert 40 mi/h into feet. Since there are 5,280 feet per mile, you have to do 5,280 x 40, which is 211,200, which is the number of feet per hour. But, the question is asking for ft/min. There are 60 minutes in an hour, so you divide 211,200 by 60, which is 3,520. So, the speed of the car per minute is 3,520 feet.