We want the integral of the standard normal from -z to z to be 0.85. Let's look at some standard normal tables and pick the right one.
It's easy to find the Erf one, which is the integral of the unit normal from 0 to z. That will be exactly half of the integral from -z to z. So we look for the z value corresponding to a probability of 0.425 in that table and find
z = 1.44
Answer: 1.44
[figure from Wikipedia]
Answer:
Please find the graph in the attached file.
Step-by-step explanation:

The real part of the result is the product of the real parts of the factors and the product of the imaginary parts:
a = 15*6 - (-4)(-3) = 90 -12 = 78
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You can treat this the same as any other product of binomials except that i² = -1.
... (15 -4i)(6 -3i) = 15(6 -3i) -4i(6 -3i) = 15·6 -15·3i -4·6i +4·3i²
... = 90 -45i -24i +12i² = (90 -12) -69i = 78 -69i
Answer:
Step-by-step explanation:
3x² - 10 = 17
3x² = 27
x² = 9
x = √9 = 3
720 minutes (12 hours)
hope this helps :)