S = 9C first sentence written as an expression Where S represents the angles supplement and C represents the angles complement A + S = 180 definition of supplementary allows me to make this statement Where A is the original angle A + C = 90 definition of complimentary allows this statement now add the prior 2 statements together A + S + A + C = 180 + 90 now simplify 2A + S + C = 270 now replace S with 9C using first statement 2A + 9C + C = 270 now simplify 2A + 10C = 270 now divide both sides by 2 A + 5C = 135 now using the second statement isolate A by adding C to both sides A = 90 - C now combine the two prior statements 90 - C + 5C = 135 now simplify 90 + 4C = 135 now subtract 90 from both sides 4C = 45 now divide both sides by 4 C = 11.25 so the complimentary angle is 11.25 now take the third equation and substitute in C A + 11.25 = 90 now subtract 11.25 from both sides A = 78.75 so the original angle is 78.75 now use the second equation and substitute in A 78.75 + S = 180 now subtract 78.75 from both sides S = 101.25 so the suplimentary angle is 101.25
After h hours A has 6000 - 2000h cells and B has 2000 - 1000h. Equating them as one form: 6000 - 2000h = 2000 - 1000h -2000h + 1000h = 2000 - 6000 -1000h = -4000 h = -4000/-1000 = 4 hours
