Question

Can someone please help me with these two questions pleasee

Answer 1

7. 62.8 sq.in.

8. 21.2 sq.in.

Explanation:

The formula of an area of a triangle:

`A_\triangle=(1)/(2)ab\sin\theta`

a, b - adjacent sides

θ - included angle

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7.

a = 9in, b = 14in, θ = 85°

sin85° ≈ 0.9962

Substitute:

`A_\triangle=(1)/(2)(9)(14)\sin85^o=(1)/(2)(126)(0.9962)\approx62.8 in^2`

8.

a = 12 in, b = 5 in, θ = 135°

sin135° = sin(180° - 45°) = sin45° ≈ 0.7071 used sin(180° - x) = sin(x)

Substitute:

`A_\triangle=(1)/(2)(12)(5)\sin135^o=(1)/(2)(60)(0.7071)\approx21.2\ in^2`