Answer:
48 cm
Step-by-step explanation:
Given:
Distance of rod from the wall = 45 cm
Distance of rod from the light = 15 cm
Length of rod = 12 cm
We can see that <DAM and <BAF are equal
Also, <DMA and <BFM are equal because they are corresponding angles
To find the length of the shadow, let's take the equation

Where.:
DM = ½ of length of the rod = ½*12 = 6
A.F = 15 + 45 = 60 cm
AM = 15 cm
Therefore,


Cross multiplying, we have:
15 * B.F = 60 * 6
15 * B.F = 360

BF = 24 cm
The shadow on the wall =
2 * BF
= 2 * 24
= 48 cm
The shadow on the wall is 48 cm
a, b, c - side lengths (a ≤ b ≤ c)
If
, then is Obtuse triangle.
If
, then is Right triangle.
If
, then Acute triangle.

Check to see if the sum of the first two sides is greater than the third.

, therefore is Scalene triangle.

It's Obtuse triangle.
Answer:
<em>Scott will take 221 minutes to run 52 km</em>
Step-by-step explanation:
<u>Speed</u>
The speed of an object can be calculated with the formula:

Where d is the distance traveled and t is the time taken.
Scott can run d=20 km in 85 minutes. Thus, his speed is:

Now he wants to know how many minutes it will take him to run d=52 km. Solving the formula for t:

Since the speed has been already determined:

Multiplying by the reciprocal of the denominator:

t = 221 min
Scott will take 221 minutes to run 52 km
Answer:
Due to the higher z-score, David has the higher standardized score
Step-by-step explanation:
Z-score:
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.
Which student has the higher standardized score
Whoever had the higher z-score.
David:
Scores on Ms. Bond's test have a mean of 70 and a standard deviation of 11. David has a score of 52 on Ms. Bond's test. So 



Steven:
Scores on Ms. Nash's test have a mean of 64 and a standard deviation of 6. Steven has a score of 52 on Ms. So 



Due to the higher z-score, David has the higher standardized score

is a parabola (looks like the letter U).
The letter a represents the coefficient of

and it controls two things (1) how wide or narrow the parabola is and (2) whether it is concave up (like a U) or concave down (like an up-side-down).
The absolute value of a (the number without the sign) controls how wide or narrow it is. If the absolute value is a fraction less than 1 the graph gets wider. The smaller the absolute value of the fraction the wider the graph gets.
If the absolute value of a is greater than 1 the graph gets narrower (it gets skinnier). The bigger the absolute value the narrower the graph.
So, if all the graphs look like a U (concave up) then the one with the smallest a is the one that is the widest.
The a also controls whether the graph is concave up or concave down. If a is negative
If a is negative the graph is concave down so any graph that is concave down has a smaller value of a than any graph that is concave up. However, if the graph is concave down the one with the smallest a would be the most narrow one.
So to find the one with the smallest a...
If they are all concave up (like a U) pick the widest one
and
If they are not all concave up pick the narrowest one that is concave down (looks like an upside down U)