Total distance John drove=450 miles
total time=8 hours
let the number of hours he drove on highway be x, number of hours he drove on turnpike will be (8-x) hours
since
distance=speed*time
distance traveled in highway=50x
distance traveled in turnpike=60(8-x)
thus the total distance will be:
50x+60(8-x)=450
simplifying the above
50x+480-60x=450
-10x=450-480
-10x=-30
thus
x=3 hours
Thus he drove on highway for 3 hours.
Cost of 3 laptops
3×546.78
=1,640.34
Cost of 2 desktop computer
2×1,255.99
=2,511.98
Cost of fax machine
125.99
Total cost
(1,640.34+2,511.98+125.99)
=4,278.31
So Kim will need an additional 778.31 to start her business
4,278.31−3,500
=778.31
Is it
3x-10= 3(-6)-10= -28
Y-5= -2-5=-7