No, in order for the lines to be parallel, the slopes have to be the same, it does not matter what the slopes are as long as they are the same slope. The lines could still be parallel if the slopes are negative.
Answer:
if 1 in= 10 miles, then, 8 in= 80 miles
Step-by-step explanation:
Answer:
a)
, b)
, c)
, d) 
Step-by-step explanation:
a) Let assume an initial mass m decaying at a constant rate k throughout time, the differential equation is:

b) The general solution is found after separating variables and integrating each sides:

Where
is the time constant and 
c) The time constant is:


The particular solution of the differential equation is:

d) The amount of radium after 300 years is:

Commutative:
a+b+c=a+c+b
1.3+23.4+3.4=23.4+1.3+3.4
Associative:
(a+b)+c=a+(b+c)
(1.3+3.4)+23.4=1.3+(3.4+23.4)