A 100-gallon tank is initially filled with pure water. Salt solution begins to flow into the tank from two sources. From one source, salt solution containing 1 pound of salt per gallon flows in at a rate of 2 gallons per minute. The second source gives 3 gallons of salt solution per minute at a decreasing concentration C(t) = 2e−2t pounds per gallon where t gives the number of minutes since the flow began. The well-mixed solution is pumped out at a rate of 5 gallons per minute. Find the mass of salt in the tank at time t.

so firstly, we need to isolate the y variables to be able to solve these inequalities. firstly, add 0.5x on both sides of the first inequality and subtract 1.5x on both sides of the second inequality:

now since the slope is positive for the first inequality, this means that the line going upwards belongs to the first inequality, and the line going downwards belongs to the second inequality.

next, since y ≥ in the first inequality, this means that the shaded region will be above the first inequality's line, thus shading regions a and b.

next, since y ≤ in the second inequality, this means that the shaded region is going to be below this line, thus shading regions a and c.

since both lines shade region a, this means that region a is the solution.

step-by-step explanation:

mark brainliest!

on monday rodney ate 1/4th of the sandwich = 3/12

on tuesday he ate 1/3rd of the sandwich = 4/12

therefore in total he has eaten = 3/12 + 4/12 = 7/12

thus we can say that he has eaten 7/12 of the sandwich on monday and tuesday alltogether.

happy to

pls mark as brainliest.

probably the last option

step-by-step explanation: