Solve
-When Making a Telephone Call Using a Calling Card $\$ 2.10$

Multiple Choice

Solve.
-When making a telephone call using a calling card, a call lasting 4 minutes costs $\$ 2.10$ . A call lasting 11 minutes costs $\$ 4.90$ . Let $y$ be the cost of making a call lasting $x$ minutes using a calling card. Write a linear equation that relates cost $y$ to time $x$ .

A) $y = 0.4 x - 6.1$
B) $y = 0.4 x + 0.5$
C) $y = - 0.4 x + 3.7$
D) $y = \frac { 5 } { 2 } x - \frac { 79 } { 10 }$