Question

Find the area of the triangle to the nearest tenth . Pleaseeee help

Answer 1

Answer:

15.8 cm²

Step-by-step explanation:

Please see attached photo for diagram.

We'll begin by calculating the angle A. This can be obtained as follow:

B = 56°

C = 78°

A =?

A + B + C = 180 (Sum of the angle in triangle)

A + 56 + 78 = 180

A + 134 = 180

Collect like terms

A = 180 – 134

A = 46°

Next, we shall determine the value of b by using the sine rule. This can be obtained:

Side opposite angle C (c) = 7.2 cm

Angle C = 78°

Angle B = 56°

Side opposite angle B (b) =?

b/Sine B = c/sine C

b/Sine 56 = 7.2/Sine 78

Cross multiply

b × Sine 78 = 7.2 × Sine 56

Divide both side by Sine 78

b = 7.2 × Sine 56 / Sine 78

b = 6.1 cm

Finally, we shall determine the area of the triangle. This can be obtained as follow:

Side opposite angle C (c) = 7.2 cm

Side opposite angle B (b) = 6.1 cm

Angle A = 46°

Area (A) =?

A = ½bcSineA

A = ½ × 6.1 × 7.2 × Sine 46

A = 15.8 cm²

Therefore, the area of the triangle is 15.8 cm²