Answer:
11700 mm²
Step-by-step explanation:
A rectangle is a quadrilateral with two equal, opposite and parallel sides. Each of the angles in a rectangle is 90°.
The horizontal distance of the rectangle = r + r + r + r = 4r
The vertical distance = r + h + r = 2r + h
Where h is the distance between the midpoint of the 2 up circles and the midpoint of the down circle.
Using Pythagoras:
(2r)² = h² + r²
h² + r² = 4r²
h² = 3r²
h = √3r²
h = r√3
Vertical distance = 2r + h = 2r + r√3
Area of rectangle = vertical distance * horizontal distance
Area = 4r * (2r + r√3) = 8r² + 4r²√3 = 4r²(2 + √3)
Substituting:
Area = 4r²(2 + √3) = 4(28²)(2 + √3) = 11703.711 mm²
Area = 11700 mm² to 3 s.f
5a)
2x + 94 = 7x + 49 (vertical angles are equal)
2x - 7x = -94 + 49
-5x = -45
x = 9
Answer
9
5b)
4y + 7x + 49 = 180 (supplementary angles, sum = 180)
4y + 7(9) + 49 = 180
4y + 112 = 180
4y = 68
y = 17
Answer
17
6)
x = 6x - 290 (vertical angles are equal)
-5x = -290
x = 58
Answer
58
I think its C. 5 that equals K.