Question 944445
1) {{{y=0.8+0.2(4)=0.8+0.8=1.6}}}
2) {{{y=0.8+0.2(5)=0.8+1.0=1.8}}}
3)
{{{drawing(300,300,-2,14,-2,6,grid(1),green(line(-10,3,20,3)),blue(line(-10,1.5,20,1.5)),circle(3.5,1.5,0.25),circle(11,3,0.25),line(0,0.8,20,4.8))}}}

a) When the cost is 3 pounds, follow the green line until it intersects.
Looks like about 11 miles.
Verify using the equation.
{{{0.8+0.2x=3}}}
{{{0.2x=2.2}}}
{{{x=11}}}
.
.
b) When the cost is 1.5 pounds, follow the blue line until it intersects.
Looks like about 3.5 miles.
{{{0.8+0.2x=1.5}}}
{{{0.2x=0.7}}}
{{{x=3.5}}}