If the following system has a solution, what is the x − coordinate of the solution?
4x + 8y = 60
x + 8y = 30

a. 6
b. 10
c. 618
d. 730
e. the system has no solution

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