Can someone me with this: simplify 17 and 9/4

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days

What is the result of adding the system of equations? 2x+y=4 3x-y=6

Solve each quadratic equation by factoring and using the zero product property. n^2 - 49 = 0