Let "radical 2" be represented by "r."
Then you are to simplify 4r + 7r - 3r. This comes out to 11r - 3r = 8r.
The answer is 8 radical 2.
Since you mentioned the fundamental counting principle, I assume you are looking for the total number of possibilities.
If you are picking a month, there are 12 options.
If you are selecting a day of the week, there are 7 options.
If you are doing both, you multiply the two numbers together.
12 x 7 = 84
5x + 2y =9
X + y= -3
5x+2y=9
2x+2y=-6
__________
3x =15
X =5
5+y=-3
Y=-8
Answer is : (5,-8)
