Solve 3x2 – 18x + 5 = 47 for x.
2 answers:
Answer:
x = 3 +√23 and x = 3 - √23
Step-by-step explanation:
The given equation 3x^2 -18x +5 = 47
This can be written as 3x^2 -18x + 5 - 47 =0
3x^2 -18x - 42 = 0
Here we have to use the quadratic formula.
x =
From the given equation, a = 3, b = -18 and c = -42
Plug in these values in the above formula, we get
x =
x =
Simplifying the above expression, we get
x = 3 +√23 and x = 3 - √23
Hope this will helpful.
Thank you.
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Answer:
P = (2, 3)
Step-by-step explanation:
P is a local minimum, so can be found from the upper zero of the derivative.
y' = 0 = 3x^2 -8x +4
0 = (3x -2)(x -2)
x = 2/3, x = 2
So, the x-coordinate of P is 2. The y-coordinate is found by evaluating the function:
y = ((x -4)x +4)x +3 = ((2 -4)2 +4)2 +3 = 3
The coordinates of P are (2, 3).
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A graphing calculator confirms this result.
