Hi there!
Since one of the angles in this set of 2 lines is a right angle, we know that every other angle is a right angle because vertical angles are congruent and that because each line has a total of 180 degrees.
Thus, Angle NDA and RDY are both 90 degrees and add up to 180 degrees.
Since the two angles add up to 180, they are supplementary angles.
Also, we should notice that those two angles are across each other. Thus, they are also vertical angles.
Your answers are choices B and C.
Have an awesome day! :)
7... if you list the factors of all 3 of this number... you will see 7 is the common factor... because:
7x3=21
7x6=42
7x9= 63
If John charge $12 then he has 14 students, and he gets $ 14*12,
If he increases on $2(12+2) , he loses 1 student (14-1), gets (12+2)*(14-1)
if he increases on he loses 2 students (14-2) gets (12+2*2)(14-2)
2+2 (12+2*2)
if he increases 2*3 he loses 3 students, (14-3) gets (12+2*3)(14-3)
2x*3 (12+2*3)
and so on......
if he increases 2*x, he loses x students, (14-x)left, gets (12+2x)(14-x)
(12+2x)
So , his revenue in general =
(12+2x)(14-x)=12*14-12x+28x-2x²=-2x²+16x+168
<em> I think it should look like this
</em>c(x)= -2x²+16x+168