Answer:
a. y = 2/5x + 1/5
Step-by-step explanation:
In point-slope form, the equation of a line with slope m through point (h, k) can be written
y = m(x -h) +k
Then a line with slope 2/5 through the point (-3, -1) will have point-slope equation ...
y = (2/5)(x +3) -1
This can be simplified to the desired form:
y = 2/5x +6/5 -1 . . . . . . eliminate parentheses; next, collect terms
y = 2/5x + 1/5
Answer: -2
Step-by-step explanation:-2
Answer:
The percentage of students who scored below 620 is 93.32%.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
Percentage of students who scored below 620:
This is the pvalue of Z when X = 620. So
has a pvalue of 0.9332
The percentage of students who scored below 620 is 93.32%.
Did somebody say you're supposed to draw the graph of the equation ?
Is that the assignment ?
OK. Just like every other equation you need to graph, get it in the
standard form, where 'y' is all alone on one side, and everything else
is on the other side. When you do that, you'll be able to spot the slope
and y-intercept of the line, or get some points, or whatever you want.
4y + 12 = 0
Subtract 12 from each side: 4y = -12
Divide each side by 4: y = -3
There's the equation you can handle.
The y-intercept is -3, and the slope is zero.
Would you like some points ? OK. Pick a couple of values for 'x',
and calculate the value of 'y' for each one:
The first value I picked for 'x': x = 72
The equation is y=-3, so when x=72, y=-3. The point is (72, -3)
The second value I picked for 'x' is: x = 1
The equation is y=-3, so when x=1, y=-3. The second point is (1, -3).
The third value I picked for 'x' is 4 billion.
The equation is y=-3, so when x=4 billion, y=-3. The third point is (1, -3).
Do you see what's going on here ? Your original equation didn't even
have 'x' in it, so we could tell right away that when the graph is drawn,
the value of 'y' at every point can't depend on 'x'.
When we simplified the equation and got it in standard form, we found that
the slope of the graph is zero. That means the graph doesn't rise or fall ...
it's just a horizontal line. Sure enough, the height of points on the line
doesn't depend on 'x'. The value of 'y' at every point on the line is -3 .
