Subscript notation is frequently used for working with larger systems of equations. Use a matrix approach to solve the system. Express the solutions as 4-tuples of the form (x1, x2, x3, x4). x1 − 3x2 − 2x3 + x4 = −6 −2x1 + 7x2 + x3 − 2x4 = −1 3x1 − 7x2 − 3x3 + 3x4 = −8 5x1 + x2 + 4x3 − 2x4 = 24 (x1, x2, x3, x4) =

At a constant it will take one hour to travel 32 mi.at that speed it will take 1/2 hr to travel the remaining 16 mi.it will take 1+1/2 hr to travel the 48mi @ 32mph.so 1 hr = 60 min& 1/2 hr = 30 min1+1/2 hr = 90 min.there are 60s in each 90 × 60 = 3600 seconds.the real question seriously is he why are they driving so slow? ! lol.