Step-by-step explanation:
It is given that,
Sam opened a savings account with a deposit of $50. Every month after that, he deposited $20 more.
It is not a proportional relationship. As initial amount was $50 and every month he deposited $20 more. The ratio is not constant for the deposited amounts.
To make the relationship proportional, he must start with zero balance and then should have deposited $20 every month.
Answer:
C
Step-by-step explanation:
Equation:

Answer:
D
Step-by-step explanation:
On the right hand side it should be m(x-x1)
Y-4=-3(x-5)
Y=-3x+19
Answer:
dA/dt= 12-2A(t)/900+t
Step by step Explanation:
Given:
rate of 3 gal/min
concentration of the solution entering is 4 lb/gal,
The equation of the solution can be expressed as
dA/dt = R(1)- R(2)
Where R(1)=( concentration of the salt at inflow* rate of input of given brine)
R(2)= ( concentration of the salt at inflow* rate of output of given brine)
R(1)= 3 gal/min× 4 lb/gal=12Ib/min
But the solution is been pumped slowly, the rate of the accumulation can calculated as;
(3 gal/min- 2 gal/min)=1gal/min
But after t min we will be having 900+t gallons present in the tank
CHECK THE ATTACHMENT FOR COMPLETE EXPLANATION