Answer:
Step-by-step explanation:
If congruent the sides are equal
15x-9=7x+11
8x=20
x=20/8=2.5
The first raise was a 25% increase, while the second raise was a 32% increase so there was a 7% increase from the first raise to the second one.
3x²-8x+4=0
(3x-2) (x-2)=0
x=2/3 , x = 2
Hence, the polynomial has two positive roots.
Option A is the correct choice.
Since the dice are fair and the rolling are independent, each single outcome has probability 1/15. Every time we choose

We have
and
, because the dice are fair.
Now we use the assumption of independence to claim that

Now, we simply have to count in how many ways we can obtain every possible outcome for the sum. Consider the attached table: we can see that we can obtain:
- 2 in a unique way (1+1)
- 3 in two possible ways (1+2, 2+1)
- 4 in three possible ways
- 5 in three possible ways
- 6 in three possible ways
- 7 in two possible ways
- 8 in a unique way
This implies that the probabilities of the outcomes of
are the number of possible ways divided by 15: we can obtain 2 and 8 with probability 1/15, 3 and 7 with probability 2/15, and 4, 5 and 6 with probabilities 3/15=1/5
I think it is c. but i'm not sure