1st letter can be any of 5 letters
2nd letter can be 5-1 any of 4 letters
5*4 = 20
there are 20 possible passwords
This is a modulus inequality.
First part: when (6x + 2) is positive
6x + 2 < 10
6x < 10 - 2
6x < 8
x < 8/6
x < 4/3
Second part: when (6x + 2) is negative.
-(6x + 2) < 10 Divide both sides of inequality by -1 and change the sign.
(6x + 2) > -10
6x + 2 > -10
6x > -10 - 2
6x > -12 Divide both sides by 6.
x > -12/6
x > -2.
Combined solution: x < 4/3 and x > -2
-2 < x < 4/3.
Graph is a line on the number line between -2 and 4/3.
-2 and 4/3 are excluded from solution.
2+6g=11-3g
-2+3g -2+3g
9g=9
--- ---
9. 9
G=1
First, to make things easier, let's turn 5/4 into a decimal given a second is equal to 1000 milliseconds.
5/4 = 1,25
1,25 * 1000 = 1250 milliseconds = 1.25 seconds
So, we've found that 45 yards can be covered in 1.25 seconds. Now we'll use the rule of 3:
45 - 1.25
80 - x
Now we solve:
(80 * 1.25) / 45 = x
100 / 45 = x
2,22... = x
So, according to our answer, 80 yards can be covered in 2,22 seconds, which in fractions would be:

Hope it helped,
BioTeacher101