Answer:
xy = 28
Step-by-step explanation:
The formula for inverse variation is
xy =k
If y = 4 and x = 7
4*7 = k
28 = k
The equation is xy = 28
to find the slope for the first one, use the formula 
(It's the slope formula)
so... 
then plug in... 
this line has a slope of 0
As for the miles problem, to find mph, the miles have to be at 1.
so... 
therefore, he drove 60.5 mph
Answer:
336 sq un
Step-by-step explanation:
The area of a rhombus is pq/2 where p and q are the diagonals.
you have:
p = 12 + 12 = 24
q = 18 + 10 = 28
so the formula would be:
24 * 28 / 2 = 336 sq un