Answer:
x < -4 or x > 7.
Step-by-step explanation:
We first determine the critical points by solving x^2 - 3x - 28 = 0:
x^2 - 3x - 28 = 0
(x - 7)(x + 4) = 0
x = 7, - 4
so the critical points are -4 and 7.
Create a Table (pos = positive and neg = negative):
Value of x< - 4 -4 < x < 7 x > 7
---------------------|----------- |--------------------- |---------------------
x + 4 NEG POS POS
x - 7 NEG NEG POS
(x + 4)(x - 7) POS NEG POS
So the function is positive (>0) for x < -4 or x > 7.
You can also do this by drawing the graph of the function.
Answer:
-2.61803398875, -0.38196601125
or
(-3±√5)/2
Step-by-step explanation:
First, expand. (2x+3)² = 4x²+12x+9=5
4x²+12x+4 = 0
Quadratic equations take the form ax²+bx+c = 0
In this case,
a = 4
b = 12
c = 4
You can solve with the equation x=(-b±√b²-4ac)/2a
Plug in:
(-12±√144-64)/8
(-12±√80)/8
(-12±√2^4×5)/8
(-12±4√5)/8
(-3±√5)/2
Final answer x = (-3±√5)/2
If you want decimal form: -2.61803398875, -0.38196601125
Answer:
D. These results do not provide good statistical evidence that taking ginkgo tablets twice a day provides some improvement in mental performance. If 200 tests are being performed at the 5% significance level, some are bound to show statistically significant results, even if the treatment does not have any effect. It is premature to draw statistical conclusions from this study in which the percentage of significant tests is about 5%.
Step-by-step explanation:
It is not right to just made a conclusive argument on a large population by considering the outcome of the analysis made on a sample of the population. In addition, based on the number of tests conducted with about 5% significance level, it is clear that this can not be used to draw the necessary conclusion.
Answer:
$560.00
Step-by-step explanation:
Let b represent Tony's average daily balance. The finance charge is computed from ...
... finance charge = 2.25% × b
We can fill in the given value and divide by the coefficient of b.
... $12.60 = 0.0225b
... $12.60/0.0225 = b = $560.00
Tony's average daily balance was $560.00.
Answer:
x = 3
y = 0
z = 8
Step-by-step explanation:
a) 3x + 3y - z = 1
b) z = 8
c) -x -3y + 2z = 13
a) 3x + 3y - 8 = 1 (substitution)
a) 3x + 3y = 9
c) - x - 3y + 2(8) = 13 (substitution)
c) -x - 3y + 16 = 13
c) -x - 3y = -3
(3x + 3y = 9) + (-x -3y = -3)
= 2x = 6
x = 3
a) 3(3) + 3y - 8 = 1
9 + 3y - 8 = 1
y = (1 -9 + 8)/3
y = 0
