Answer:
11,800 different four letter permutations can be formed using four letters out of the first 12 in the alphabet
Step-by-step explanation:
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:

In this question:
Permutations of four letters from a set of 12 letters. So

11,800 different four letter permutations can be formed using four letters out of the first 12 in the alphabet
Answer:
Step-by-step explanation:

Answer:
x = 
Step-by-step explanation:
The altitude of the triangle must equal 4 because it is a right triangle with another leg of 3 and a hypotenuse of 5 (reason is due to the pythagorean theorem)
Therefore, the triangle on the right has legs of 4 and 7 and, again, use the phythagorean theorem to find 'x' (the hypotenuse)
+
= 
16 + 49 = 
65 = 
x = sq rt 65
Answer:
15
proof on pic......................
Set each expression from the parentheses equal to 0 separately like so:
Equation 1: x - 4 = 0
Equation 2: -5x + 1 = 0
Now for each equation solve for x!
Equation 1:
x +(- 4 + 4) = 0 + 4
x = 4
Equation 2:
-5x +( 1-1) = 0 - 1
-5x/ -5 = -1 / -5
x = 1/5
Check:
(4 - 4)(-5*4 + 1)
(0) (-20 + 1)
(0) (-19)
0 = 0 -------------------------> correct!
(1/5 - 4)(-5 * 1/5 + 1)
(-19/5)(-1 + 1)
(-19/5)(0)
0 = 0 -------------------------> correct!
smaller x = 1/5
larger x = 4
Hope this helped!