Answer:
54.6 cm : B
Step-by-step explanation:
Mathematically the area of a rectangle is 2( l + b)
So in practical terms we only need the measure of two sides as we have 2 equal sides for a rectangle.
We can see that we have two right angles on each sides
Now to find b, we can use trigonometric ratios
For each of the rectangles, the diagonal represents the hypotenuse
Mathematically;
sin 30 = b/20
From triangle ABC
b = 20 sin 30 = 20 * 0.5 = 10 cm
Now, to get l
Mathematically;
Sin 60 = l/20
l = 20 sin 60 = 17.32 cm
So the perimeter is;
2(10 + 17.32)
2(27.32) = 54.64 cm which is 54.6 to the nearest tenth
