To do this, we must allow this hidden number to be x.
2x + 4 = 8
Now we will solve by first subtracting 4 from each side:
2x = 4
Now we will divide each side by 2 to isolate the variable:
x = 2
Therefore, the mystery number is 2.
Answer: 
Step-by-step explanation:
Given : The total number of cards in a deck = 52
Number of red cards = 26
There are two types of red cards : diamond and heart.
Number of diamond cards = 13
The probability that the first card is a diamond :-

Since diamond is also a red card.
Now, the total cards left = 51
The number of red cards left = 12
The probability that the second card is a red card (without repetition) is given by :-

Now, the probability of choosing a red card for the second card drawn, if the first card, drawn without replacement, was a diamond :-

The answer is 2. I hope this helps.
Answer:

Step-by-step explanation:

The answer would be C because the middle point, which is F should be in the middle when naming the angle