2/5 = 42
1/5 = 21
5/5 = 105
105 students in the class
4^(12-4x)=256 realize that 256 is 4^4 so we really have:
4^(12-4x)=4^4 taking the natural log of both sides
(12-4x)ln4=4ln4 dividing both sides by ln4
12-4x=4 subtract 12 from both sides
-4x=-8 divide both sides by -4
x=2
Circumfrence: pi times diameter
7.9*
circumfrence is approximatley 24.806
area:
a=
*(1/2(d))^2
a= 48.99
Answer:
none of them are perpendicular or parallel