Answer:
c.7,999,999
Step-by-step explanation:
The phone number is of the form ABC - XXXX
A can be any number from 2 - 9. This means number of possible values for A are 8.
The rest of the places B,C and X can be any digit from 0 - 9. This means there are 10 possible values for each of these.
Since, value to A can be assigned in 8 ways, and to the rest of the 6 positions in 10 ways, according to the fundamental rule of counting, the total number of possible phone numbers that can be formed will be equal to the product of all the individual ways:
Total possible phone numbers = 8 x 10 x 10 x 10 x 10 x 10 x 10
Since, 1 of the given number: 867-5309 is not used, the total possible phone numbers will be:
Total possible phone numbers = 
Hence, option C: 7,999,999 give the correct answer.
Two angles are said to be suplementary when the aum of the two angle is 180*
Pick any two pairs of equations<span> from the system. Eliminate the same </span>variable<span> from each pair using the Addition/Subtraction method. Solve the system of the two new </span>equations<span> using the Addition/Subtraction method.</span>
Remmeber, you can do anything to an equation as long as you do it to both sides
for inequalities, if you multiply or divide both sides by a negive, flip the direction of the inequality sign
pemdas always applies
but also the commutative property and assiociative property
so
2(5y+13)-6<20
add 6 both sides
2(5y+13)<26
divide both sides by 2 (easier that distributing)
5y+13<13
minus 13 both sides
5y<0
y<0 is the solution
If you just want to know what is the least common multiple of 20 and 15, it is 60. Usually, this is written as
lcm(20,15) = 60
