Find the area of ΔABC.
A)21.93
B) 37.20
C) 29.77
D) 18.6
Answer:
Option D is correct
Step-by-step explanation:
First, let's find side BC by using Pythagoras theorem.
Given:
=> 9² = 7.8² + x²
=> 81 = 60.84 + BC²
=> BC² = 20.16
=> √BC² = √20.16
=> BC = √20.16
=> BC = 4.48998886413 (Using calculator)
=> BC ≈ 4.49 (Estimated)
Therefore, side BC ≈ 4.49 units. Now, let's find the area by using hero's formula.
=> 1/2(Perimeter) = S
=> Perimeter: Hypotenuse + Side 1 + Side 2
=> 7.8 + 9 + 4.49
=> 21.29 = Perimeter
=> 1/2(21.29) = S
=> 10.645 = S
=> √s(s - a)(s - b)(s - c) = Area of triangle
=> √10.645(10.645 - 9)(10.645 - 4.49)(10.645 - 7.8)
=> √10.645(1.645)(6.155)(2.845)
=> √10.645 x 1.645 x 6.155 x 2.845
=> √306.635120999 (Using calculator)
=> √306.64 (Estimated)
=> 17.5111393119 (Using Calculator)
=> 17.51 units² (Estimated)
We can see that option D is the closest option. Therefore, Option D is correct.
If Option D was incorrect, then my second opinion is A.
If both are wrong, I deeply apologize for the inconvenience caused by me. Hoped this helped.
Answer:
answer is d) 18.6
Step-by-step explanation:
area = 1/2ab sin ∅
a= 9
b = 7.8
so it's
1/2 ×7.8 × 9 sin 32
use your calculator to get 18.600 unit squared
*we can also use the heroes formula*...