The graph will cross at the coordinates (-2, 9)
<h3>How to solve equations?</h3>
y = 3x + 15
y = 3 - 3x
y = 3x + 15
Hence,
when x = 2
y = 3(2) + 15 = 21
when x = 0
y = 3(0) + 15 = 15
y = 3 - 3x
when x = 2
y = 3 - 3(2)
y = 3 - 6
y = -3
when x = 0
y = 3 - 3(0)
y = 3
Therefore, let's check if the equation will cross.
y = 3x + 15
y = 3 - 3x
using substitution,
3 - 3x = 3x + 15
3 - 15 = 3x + 3x
- 12 = 6x
x = -12 / 6
x = -2
y = 3 - 3(-2)
y = 3 + 6
y = 9
Therefore, the graph will cross at the coordinates (-2, 9)
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Standard form for y+7=-2/5(x-10) is y=-7-2/5(x-10)
1 cup = 8 fluid ounces.
6.875 cups = ? fluid ounces.
8*6.875=55.
Your answer would be 55 fluid ounces.
The question is incomplete! Complete question along with answer and step by step explanation is provided below.
Question:
The lifetime (in hours) of a 60-watt light bulb is a random variable that has a Normal distribution with σ = 30 hours. A random sample of 25 bulbs put on test produced a sample mean lifetime of = 1038 hours.
If in the study of the lifetime of 60-watt light bulbs it was desired to have a margin of error no larger than 6 hours with 99% confidence, how many randomly selected 60-watt light bulbs should be tested to achieve this result?
Given Information:
standard deviation = σ = 30 hours
confidence level = 99%
Margin of error = 6 hours
Required Information:
sample size = n = ?
Answer:
sample size = n ≈ 165
Step-by-step explanation:
We know that margin of error is given by
Margin of error = z*(σ/√n)
Where z is the corresponding confidence level score, σ is the standard deviation and n is the sample size
√n = z*σ/Margin of error
squaring both sides
n = (z*σ/Margin of error)²
For 99% confidence level the z-score is 2.576
n = (2.576*30/6)²
n = 164.73
since number of bulbs cannot be in fraction so rounding off yields
n ≈ 165
Therefore, a sample size of 165 bulbs is needed to ensure a margin of error not greater than 6 hours.
Answer:
wea did tha r come from??
Step-by-step explanation:
it is supposed to be d
