Answer:
68.0°
Step-by-step explanation:
The tangent function relates the sides of a right triangle to the angle:
Tan = Opposite/Adjacent
The mast is opposite the angle of elevation, and the shadow is adjacent, so you have ...
tan(angle) = (42 ft)/(17 ft)
The inverse tangent function is used to find the angle whose tangent is a particular value.
angle = arctan(42/17) ≈ 67.964°
The angle of elevation is about 68.0°.
A good estimate would be -10.
In order to estimate, start off by rounding both numbers to the nearest whole number. -7.94 can be rounded to -8 because the first number to the right of 7 is greater than 5. 2.31 can be rounded to 2 because the first number to the right of the 2 is less than 5.
After rounding, the expression becomes -8-2, which is equal to -10.
Answer:
At a price of $p, a quantity, q, of the item is sold.
If q = f(p)
(a) f(150) = 2000 means at price = 150$, the number of items sold is 2000
(b) f'(150) = -25 means rate of sale is negative or the number of items sold will be decreases in future
9. You can easily get rid of the decimal fraction by multiplying by 10. This will move the decimal point one place to the right in each number.
However, since all the decimal fractions are even numbers of tenths, you can also turn them to integers by multiplying by 5:
... 3x +24 = 36
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10. If you can't describe what the parts of your equation represent, you have no business writing it. Saying you can't describe your equation is the same as saying you don't understand the problem.
It is important to be able to describe the parts of the equation just as it is important to be able to say what the problem is telling you, what it is asking, and what your strategy is for solving it. The parts of the equation are intimately tied with those things: they embody the given information and the strategy of your solution.