Replace each letter with it's value, so:
= (5*-2) + (-3*2) + 3
= -10 -6 +3
= -13
Let there be 2x science and 5x art books
<span>science books sold = 2x × 0.2 = 0.4x </span>
<span>science books unsold = 2x – 0.4x = 1.6x </span>
<span>art books sold = 5x × 0.2 = x </span>
<span>art books unsold = 5x – x = 4x </span>
<span>total books unsold = 1.6x + 4x = 5.6x </span>
<span>5.6x = 2240 </span>
<span>x = 400 </span>
<span>2x science = 800 </span>
<span>and 5x art books = 2000 </span>
Answer: Choice B
12.5 < x < 18.9
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Explanation:
We have a triangle with these side lengths:
- a = 10
- b = 16
- c = x = unknown
Let's assume that b = 16 is the largest side of this triangle.
By the converse of the pythagorean theorem, we need 
to be true in order for an acute triangle to happen.
So,
Now let's consider the possibility that the missing side x is actually the longest side.
Using the same theorem as before, we would say,
We found that x > 12.5 and x < 18.9
This is the same as saying 12.5 < x and x < 18.9
Put together, they form the approximate answer of 12.5 < x < 18.9
<span>There are 100 * 99 = 9900 different ways to choose two students out of 100 bandmembers. You and our brother are 2 of that ways: you being selected first and you being selected second. Therefore the probability that you two are selected is 2 / 9900 = 0,000202. You can also think as the probability of you being selected among 100 bandmembers, which is 1/100, times the probability of your brother being selected among 99 members, which is 1/99 => (1/100) * (1/99) = 1/ (100*99) = 1 / 9900; plus the same for your brother being selected first and you second => [1/9900] * 2 = 2/9900, which is the same calculated above.</span>
Answer: 187.30
explanation for answer:
