First, some defintions
reciprocals are like a/b and b/a or 5/1 and 1/5
remember,

john's fraction is reciprocal of sarah's
john=a/b
sarah=b/a
david multiplies his by sarah and gets 12/35
(b/a)(david)=12/35
multplies his number by john and gets 12/35
(a/b)(david)=15/7
hmmm
(b/a)(david)=12/35 and
(a/b)(david)=15/7
if we divide them then we do





square root both sides

therefor
b=2 and a=5
john's number is a/b=5/2
sarah's number is 2/5
david, hmm
sarah times david=12/35
2/5 times david=12/35
times both sides by 5/2
david=60/70
david=6/7
check other
john times david=15/7
5/2 times 6/7=15/7
30/14=15/7
15/7=15/7
true
sarah's favorite number is 2/5
john's favorite number is 5/2
david's favorite number is 6/7
The side opposite the right angle.
Right because if you make a triangle like that than you make a right a right angle
When you plot the offered points on the graph, you find only one of them falls inside the shaded region:
... D. 43 pepperoni slices and 25 cheese slices
The answer to this question is B!