Answer:
n = -5, 3.
Step-by-step explanation:
n^2 + 2n - 15 = 0
Let's check if we can factor this quadratic:
We need 2 numbers whose product is -15 and whose sum is +2.
There are 2 such numbers and they are +5 and -3, so the factors are:
(n + 5)(n - 3) = 0.
n + 5 = 0 or n - 3 = 0
therefore the zeroes are -5 and 3.
Since the sample is greater than 10, we can approximate this binomial problem with a normal distribution.
First, calculate the z-score:
z = (x - μ) / σ = (37000 - 36000) / 7000 = 0.143
The probability P(x > 37000$) = 1 - P(<span>x < 37000$),
therefore we need to look up at a normal distribution table in order to find
P(z < 0.143) = 0.55567
And
</span>P(x > 37000$) = 1 - <span>0.55567 = 0.44433
Hence, there is a 44.4% probability that </span><span>the sample mean is greater than $37,000.</span>
(0,2),(-2,-1),(2,5)
-3x+2y=2
+3x +3x
2y/2=3x+2/2
y=1 1/2x+2
Plug in numbers for x then solve for y
