(High points) please find x and explain

What other information do you need to prove triangle dac=bca by asa

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

How do i put 3(x+7) in distributive property