when making a phone call using a calling card a call lasting 6 minutes cost $1.60. a call lasting 13 minutes cost $3.00. Y=cost and X=minutes. Write a linear equation. predict how much a 25 minute call cost?

so using the first pair (6,1.6)

we'll write:

Y-1.6=0.2(X-6)

so a 25 minute call will cost...

$5.40