Answer:2.5 miles per hour
Reason: Your traveling at 2.5 miles per hour for a total of 4 hours.
Equation :
[x(x+4)]/2=6 (as (b*h)/2=A)
x*x + 4*x -12 = 0
so, x = 2 units(as -6 is negative)
1
A coefficient is the number attached to a variable (k). In front of k is an implied 1 because k*1=k. So the coefficient of the third terms is 1