Answer:

Step-by-step explanation:
-p(d+z)=-2z+59
-pd-pz=-2z+59
lets bring all z integers on one side
-2z+pz = -pd-59
z(-2+p)=-pd-59
z = (pd-59) / (-2+p)
D = rt, Distances Equal
72t = 90(t-1)
90 = 18t
90/18 = t = 5hr
second car catch up to the first in 4hrs
1 17/20
the 1 is ur whole number....it stays ur whole number
17/20 = 0.85
so we have 1.85.....to turn it into a percent, move the decimal 2 spaces to the right = 185%
Remember property of exponents

add exponents of same base
ok so
50,000 is 5 times 10^4
so
50000 times 10^15=
5 times 10^4 times 10^15=
5 times

=
5 times 10^19