Question 785266
IF STUDYING EQUATION OF A LINE:
If {{{d}}}= distance (miles) to Philadelphia is a function of {{{t}}} = minutes driving, the equation for the function/loine is
{{{d-34=-0.85(t-43)}}} (point-slope form of the equation for the line)
For {{{t=43}}}, {{{d-34=0}}} <--> {{{d=34}}}
For {{{t=51}}}, {{{d-34=-0.85(51-43)}}}-->{{{d-34=-0.85*8}}}-->{{{d-34=-6.8}}}-->{{{d=34-6.8}}}-->{{{d=highligh(27.2)}}}
After 51 minutes of driving, Melissa will be {{{highligh(27.2)}}} miles from Philadelphia.
 
FOR FIFTH GRADERS:
Melissa is driving 0.85 miles per minute, or {{{0.85*60mph=51mph}}}).
In {{{8minutes=51minuts-43minutes}}} of driving, Mellisa would travel
{{{0.85*8miles=6.8miles}}},
so after 51 minutes of driving the distance remaining will be
{{{34miles-6.8miles=27.2miles}}},
{{{6.8miles}}} less than the 34 miles remaining after 43 minutes of driving.