9514 1404 393
Answer:
(c) 14.5 cm
Step-by-step explanation:
The relevant trig relation is ...
Sin = Opposite/Hypotenuse
sin(65°) = BC/BA
BC = BA·sin(65°) ≈ (16 cm)·0.9063 ≈ 14.501 cm
BC ≈ 14.5 cm
_____
<em>Additional comment</em>
As is often the case, a simple estimate is all that is needed to identify the correct answer choice.
You only need to know how the long side of a right triangle compares to the others. In an isosceles right triangle, both legs are √2/2 ≈ 0.71 times the hypotenuse. The long side of a right triangle will never be shorter than that. This means the long side must be greater than about 11.2, and cannot be greater than 16. There is only one answer choice in that range.
Answer:
Step-by-step explanation:
Answer:
The man traveled 20km by train.
Step-by-step explanation:
If x is the distance he traveled by train, you can write this equation to represent the situation:
Then, you can simply solve for x:
The man traveled 20km by train.
Step-by-step explanation:
the positive integer numbers that are divisible by 7 are an arithmetic sequence by always adding 7 :
a1 = 7
a2 = a1 + 7 = 7+7 = 14
a3 = a2 + 7 = a1 + 7 + 7 = 7 + 2×7 = 21
...
an = a1 + (n-1)×7 = 7 + (n-1)×7 = n×7
the sum of an arithmetic sequence is
n/2 × (2a1 + (n - 1)×d)
with a1 being the first term (in our case 7).
d being the common difference from term to term (in our case 7).
how many terms (what is n) do we need to add ?
we need to find n, where the sequence reaches 200.
200 = n×7
n = 200/7 = 28.57142857...
so, with n = 29 we would get a number higher than 200.
so, n=28 gives us the last number divisible by 7 that is smaller than 200 (28×7 = 196).
the sum of all positive integers below 200 that are divisible by 7 is then
28/2 × (2×7 + 27×7) = 14 × 29×7 = 2,842
