Question

Suppose a 5 minute call over seas cost 5.91 and a 10 minute call cost 10.86. The cost of the call and the length of the call are related

Answer 1

5.91 = m(5) + b

10.86 = m(10) + b subtract top equation from bottom

4.95 = 5m divide both sides by 5

0.99 = m

5.91 = 5(0.99) + b simplify

5.91 = 4.95 + b subtract 4.95 from both sides

0.96 = n

The base charge is 0.96

C = (0.99)M + 0.96

Substitute $12 for C and solve for M.

Step-by-step explanation: