PLS HELP I NEED THIS NOWWW ITS NOT TOO HARD (GRADE 8) find the points where the graphs of y=1-x and y=x-3 intersect algebraically

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