What is the value of x?

5

Step-by-step explanation:

Use the Pythagorean Theorem

a²+b²=c² plug in the info you have

a²+12²=13² (c is always the side opposite from the right angle)

Solve for a

a²+144=169

   -144  -144

a²=25   take the square root of both sides

√a²=√25

a=5

the answer is 175.4379

step-by-step explanation:

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.