Question

How to do this question plz ​

Answer 1

h =
`√(77)`

A =
`2√(77)`

Explanation:

Rules for solving this problem:

Isosceles triangle rules

• ∠C = ∠A
• BC = BA

Because of isosceles being made up of two right triangles; using the pythagorean theorem we can deduce that

• (1/2 x AC)² = BC² - h²
• (1/2 x AC)² = BA² - h²

Area of a triangle

• A = 1/2 (Base x Height) = 1/2 * bh

Step 1 - Find the height

`h =√(9^2 - ((1/2)AC)^2) = √(9^2 - ((1/2)~4)^2) = √(9^2 - 2^2) = √(81-4) = \sqrt {77}`

Step 2 - Find the area

`A = (1)/(2)bh = ((1)/(2))(4)(√(77)) = 2 √(77)`

Hope this helps,

- J.M.Jamon

Pennsylvania State University

Full-time B.S.CE. undergrad student

Answer 2

a) root77

b) 2 root77 / ~17.55 cm^2

Explanation:

a) by using Pythagorean Theroem,

a^2 + b^2 = c^2

2^2 + b^2 = 9^2

4 + b^2 = 81

81 - 4 = b^2

77 = b^2

root77 = b

b) 1/2bh is the quation for area thus,

area = 1/2 ( 4 ) ( root77)

area = 2 root77

or area = ~17.55 cm^2