A room can be paved with 1210 square tiles. If the side of each tile were to increase by 1 cm, it would only take 1000 tiles to pave the room. What dimension is each tile?
Let s be the side of the tile before the increase......and since the areas they cover are equal, we have:
1210s^2 = 1000(s + 1)^2 simplify
1210s^2 = 1000s^2 + 2000s + 1000 rearrange
210s^2 - 2000s -1000 = 0 divide through by 10
21s^2 - 200s - 100 = 0 factor
(21s + 10) (s -10) = 0
So s = -10/21 cm......reject ......or....... s = 10 cm
So.....the old tiles were 10 cm on each side and the "new tiles" are 11cm on each side
Let s be the side of the tile before the increase......and since the areas they cover are equal, we have:
1210s^2 = 1000(s + 1)^2 simplify
1210s^2 = 1000s^2 + 2000s + 1000 rearrange
210s^2 - 2000s -1000 = 0 divide through by 10
21s^2 - 200s - 100 = 0 factor
(21s + 10) (s -10) = 0
So s = -10/21 cm......reject ......or....... s = 10 cm
So.....the old tiles were 10 cm on each side and the "new tiles" are 11cm on each side