Prove that the value of the expression does not depend on the variable x: a) (x–5)(x+8)–(x+4)(x–1) b) x^4–(x^2–1)(x^2+1) 20 points

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.