Answer:
60cm^2
Step-by-step explanation:
We assume that is a circumscribing quadrilateral, rather than one that is circumscribed. It is also called a "tangential quadrilateral" and its area is ...
K = sr
where s is the semi-perimeter, the sum of opposite sides, and r is the radius of the incircle.
K = (12 cm) (5cm) = 60 cm²
_____
A quadrilateral can only be tangential if pairs of opposite sides add to the same length. Hence the given sum is the semiperimeter.
Answer:
Option (C)
Step-by-step explanation:
If AD is the altitude to BC, both the segments AD and BC will be perpendicular to each other.
By the property of perpendicular lines,

where
is the slope of the line AD and
is the slope of BC.



Now from the given property,


Therefore, slope of altitude BC = 
Option (C) will be the answer.