3a)
Equation of a line formula: y - y₁ = m(x - x₁)
x₁ and y₁ are coordinates of one point on the line
m is the gradient of the line
m = Δy/Δx = (y₂ - y₁)/(x₂ - x₁)
If we say:
(x₁, y₁) = (0, -1)
(x₂, y₂) = (2, 3)
then:
m = (3 - -1)/(2 - 0)
= 4/2
= 2
So, the equation of the line is (using the formula):
y - -1 = 2(x - 0)
y + 1 = 2x
y = 2x - 1
3b)
Any two given lines will always intersect unless they have the same gradient, i.e. they are parallel;
So, to determine if the two lines will intersect all we have to do is work out the gradient of the second line and see if it is the same as the the gradient of the first (which we worked out to be 2) or not;
So, for the second line:
(x₁, y₁) = (-3, 3)
(x₂, y₂) = (-2, 4)
And so:
m = (4 - 3)/(-2 - -3)
= 1/1
= 1
1 ≠ 2;
The gradients of the two lines are not the same;
They are not parallel;
They will intersect at some point.
4a)
|| Male || Female
0 ≤ x ≤ 1 || 66 || 2
2 ≤ x ≤ 7 || 583 || 160
8 ≤ x || 89 || 42
Total 738 204
x = number of times a day hand are washed
4b)
66/738 × 100 = 8.94..... ⇒ 9%
9% of males wash their hands once or less per day
2/204 × 100 = 0.980..... ⇒ 1%
1% of females wash their hands once or less per day
89/738 × 100 = 12.0..... ⇒ 12%
12% of males wash their hands 8 or more times per day
42/204 × 100 = 20.5..... ⇒ 21%
21% of females wash their hands 8 or more times per day
On average, it appears that females tend to wash their hands more frequently;
However, the fact that significantly less women reported could mean the data is not suitable to be used to compare the number of hand washes between males and females. <span />
Answer: 3520
please give brainliest
Step-by-step explanation:
Answer: Depends which one you need more.
Step-by-step explanation:
The effect of this increase <u>will reduce the variability of the estimate</u>.
<u>Step-by-step explanation</u>:
Variability of a sample can be determined with the help of variance and standard deviation. Sampling variability shows the variation in the estimate between the samples.
Variability is defined as the how close the scores in the distribution are to the middle of the distribution.
In the above scenario, the polling company increases the size of the random sample of voters before election. The proportion of the voters is estimated with the help of poll. The effect of increasing the sample is to reduce the variability of the estimate.
Answer:
The slope is 1/2
Step-by-step explanation:
m=y²-y¹/x²-x¹
m=(-8)-(-7)/4-6
m=-1/-2
m=1/2
