Answer:
He paid $1.11
Step-by-step explanation:
2.50 * 0.4 (he paid for 40% of the original price, since it was a 60% discount) = 1
1 * 0.11 (11% sales tax) = 0.11
1 + 0.11 = 1.11
When they have no solutions, the lines are parlaell, or they have the same slope but different y intercept
example
3x+2y=2 and
3x+2y=4 are paralell
also
y=3x+2 and
y=3x+4 are also parlell, no solutions
infinite solutions are when they are the same line
they have the same slope and y intercept
to find out, simplify
3x+2y=4 and
6x+4y=8 are smae lien
also
y=3x+2 and
2y=6x+4 aer the same line
1 solution is when it is none of the above things
a normal thing, where the slopes are differnet
example
y=2x+2
y=3x+2
first number and second number and third number = Total
78 possibilities x 78 possibilities x 78 possibilities = 234
Since "order" matters, this is a permutation.
So, this can be calculated using: ₇₈P₃
"Permutation lock" would be a more appropriate name.
The answer is gonna be 14