Answer:
Step-by-step explanation:
GIVEN: two two-letter passwords can be formed from the letters A, B, C, D, E, F, G and H.
TO FIND: How many different two two-letter passwords can be formed if no repetition of letters is allowed.
SOLUTION:
Total number of different letters 
for two two-letter passwords 
different are required.
Number of ways of selecting different letters from 
letters
Hence there are different two-letter passwords can be formed using letters.
Answer:
y=3x-1/5
Step-by-step explanation:
we have to move 1/5 to the other side
X-4y=-18
an easy way is to solve for oone variable
solve for x
add 4y both sides
x=4y-18
when y=1, x=-16
when y=0, x=-18
when y=2, x=-10
(x,y)
so some orderd pairs are
(-16,1)
(-18,0)
(-10,2)
The cost of each stone sphere is $ 36.81
<em><u>Solution:</u></em>
Given that,
An architect plans to buy 5 stone spheres and 3 stone cylinders
For the same amount, she can buy 2 stone spheres and 6 stone cylinders
Let "x" be that same amount
Let "a" be the cost of each stone sphere
Cost of each stone cylinder = $ 36.81
Therefore,
x = 5 stone spheres and 3 stone cylinders
x = 5a + 3(36.81)
Similarly,
x = 2 stone spheres and 6 stone cylinders
x = 2a + 6(36.81)
Equate both,
Thus cost of each stone sphere is $ 36.81
