A company has installed new machinery that will produce a savings rate (in thousands of dollars per year) of S'(x) = 225-x^2, where x is the number of years the machinery is to be use. The rate of additional costs (in thousands of dollars per year) is expected to be C'(x) = x^2-25x+150. For how many years should the company use the new machinery? Find the net savings (in thousands of dollars) over this period.

After 15 years the use of said machine is no longer profitable

Step-by-step explanation:

it should be used, as long as the money generated is not smaller as the costs generated. By setting both formulas equal (calculating the x value for when they are equal) you get x = 15 and x = -2.5(which doesnt make sense in this context).

2. angles qrt and qst both measures 156 degrees.

step-by-step explanation:  

we have been given a diagram of a circle and we are told that measure of arc qvt is 156 degrees.  

we can see from our given diagram that angle qrt and angle qst subtends to arc qvt.

since we know that angles subtended by the same arc at the circumference are always equal.

by angle subtended by same arc theorem, measure of angle qrt and angle qst will be equal to the measure of arc qvt.

therefore, angles qrt and qst both measures 156 degrees and 2nd statement is the correct choice.

yes the total will be same because in both of them the expression.is rearranged but their sign remains the same hence it hss just been shuffled