Let x be a real number.
If x>=0, then |x|=x.
If x<0, then |x|=-x.
Thus, for x=5 and x=-5, |5|=|-5|=5
Where's the figure? I can't exactly solve this question without knowing how the figure looks like. So put a picture of the figure and then I'll try to answer your question. :)
Step-by-step explanation:
DC = 12
................
The two original functions are 4x+9y=7 and 4x-9y=9
To use the combination method, add all the values of the two equations together to cancel out one of the variables
4x+4x+9y-9y=7+9
8x=16
8x/8=16/8
x=2
4(2)+9y=7
8+9y=7
8-8+9y=7-8
9y=-1
y=-
The answer is C based on SAS