Answer:

Step-by-step explanation:
we know that
Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.
so

where
a, b and c are the length sides of triangle
s is the semi-perimeter of triangle
we have

Find the semi-perimeter s

Find the area of triangle



Simplify

Answer:
D. 8.8
Step-by-step explanation:
As the pythagorean theorem.
A² + B² = C²,
5.4 × 5.4 + 7 × 7 = C²,
29.16 + 49 = C²,
78.16 = C²,
8.8 ≈ C
Answer: Losing 6 yards in a football game
Step-by-step explanation: -6 means to take away 6
and the only word problem to take away 6 is D
0.8 is greater because 3/4 equals .75
I think the answer might be B