It is C..........................Happy Birthday
(20*16 ft^2)(144 in^2/ft^2)(tiles/(10*10 in^2)
320ft^2(144in^2/ft^2)(tiles/100in^2)=460.8 tiles
However tiles are quantized integer units so 461 tiles will be needed to tile the kitchen.
<h3>
Answer: c < -13</h3>
========================================
Work Shown:
9c + 90 < -27
9c + 90 - 90 < -27 - 90 .... see note 1
9c < -117
9c/9 < -117/9 ... see note 2
c < -13
-----------
note 1: I'm subtracting 90 from both sides to undo the "plus 90" that is happening on the left side
note 2: I divided both sides by 9 to undo the multiplication. The expression 9c is the same as 9*c or "9 times c". The inequality sign will <u>not</u> flip as we are dividing both sides by a positive number.