In geometry, heron's formula (sometimes called hero's formula), named after hero of alexandria, gives the area of a triangle by requiring no arbitrary choice of side as base or vertex as origin, contrary to other formulae for the area of a triangle, such as half the base times the height. use heron's formula to find the area, in square yards, of δabc.

a. 7.746
b. 33.941
c. 30.984
d. 34.947

  D.  37.947

Step-by-step explanation:

Heron's formula makes use of the value "s", the semi-perimeter. Here, ...

  s = (7 + 11 + 12)/2 = 15

Then the area is ...

  A = √(s(s -a)(s -b)(s -c)) = √(15·3·4·8) = √1440 = 12√10 ≈ 37.947

_____

Comment on answer choices

This value is verified by a triangle solver. We suspect a typographical error in the answer choices, specifically, selection D.

1. is 4 and 2. is 3

step-by-step explanation:

so if you look at the first one you see that 1 is to 4 and 2 is to 8 and so on, so you can see for every 1 there is a times 4 so if it were 3 then it would be 3*4 and it is 12

for number 2 it is 3 because 1 is to 3 and 2 is to 6 so for every 1 there is 3 so if it were 3 then there would be 3*3 = 9

answer: download photomath it's legit.

step-by-step explanation: