Since density is the ratio of mass to (in this case) area, we can find the mass of the triangular region
by computing the double integral of the density function over
:

The boundary of
is determined by a set of lines in the
plane. One way to describe the region
is by the set of points,

So the mass is




50 calories are consumed per milefor 15 miles per hour, calories consumed
= 50*15
=750 calories per hour,
this is equal to 750/3600
= 0.2083 calories/second, given that,
1 calorie per sec
= 4.19 watt, the average power output
= 0.2083*4.19
= 0.873 Watts
7/28= 25/x
28*25= 700
700=7x
700/7=100
Use the formula (y2-y1)/(x2-x1)