Their distance differs by 15 miles for each hour of travel time. Thus, the travel time of interest is
.. (180 -144) miles/(15 miles/hour) = 2.4 hour
The red car's speed is 180 mi/(2.4 h) = 75 mi/h.
The blue car's speed is 144 mi/(2.4 h) = 60 mi/h.
We know that
in a right triangle
Applying the Pythagoras Theorem
c²=a²+b²
in this problem
c=√87 yd
a=√23 yd
b=?
so
b²=c²-a²-----> b²=(√87)²-(√23)²----> b²=87-23----> b²=64----> b=8 yd
the answer is
8 yd
150 is the amount of interest earned for one year because the formula of PRT is, in this case 5000 times 0.03 times one which gets you the answer of 150.
The answer to this is B. y=-x-5.
