Answer:
x = -5
Step-by-step explanation:
Since these two triangles are similar, the ratio between the corresponding lengths of each triangle will be the same.
This means the ratio between one side of each triangle (e.g. AD and DC) will be the same as the ratio between a different side of each triangle (e.g. BE and BC).
So, to create an equation for the sides which contain the unknown 'x', we must first find the ratio between the two sides by using a different set of sides.
On the right side we are given 9 for AD, and 18 for DC.
9/18 = 0.5
This means that the extra length of the larger triangle from the smaller one (AD) is half the length of the smaller triangle (DC). We can use this to make an equation for x:
If AD/DC = 0.5, then BE/EC will also = 0.5
BE = x+23
EC = x+41
Therefore:

Now we can solve by multiplying both sides by x+41 to eliminate the fraction:

Now we multiply out the brackets and move the terms to different sides:



And if we substitute the -5 into the equations:
-5+23 = 18
-5 + 41 = 36
We will see that -5 does indeed give us the same ratio between the lengths:
18/36 = 0.5
Hope this helped!
Answer:
The 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
For this problem, we have that:
Sample of 421 new car buyers, 75 preferred foreign cars. So 
85% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).
Answer:
y = 3
Step-by-step explanation:
We need to find the slope. We do so by choosing any two points and dividing the change in the y-coordinates (their difference) by the change in the x-coordinates (their difference). Let's just choose (1, 3) and (0, 3). The slope is: . So, the slope is 0.
We want to write a line in slope-intercept form, which is: y = mx + b, where m is the slope and b is the y-intercept (where the line crosses the y-axis). Here, the slope m = 0. Looking at the graph, we see that the y-intercept is (0, 3), so b = 3. Then, our line is: y = 0x + 3 ⇒ y = 3.
Another note is that this is a horizontal line. One thing to remember is that all horizontal lines have slopes of 0, so their function is simply y = k, where k is a constant through which the line cuts through.
Answer:
C: (1,3)
Step-by-step explanation:
If we count 1 to the right on the x-axis and count 3 up on the y-axis, we will end up at the point of intersection which is (1,3).