If you plug in the x values of both (2, 8) and (4, 12) into each equation, you'll find that y = 2x + 4 gives you the correct y values for both (2, 8) and (4, 12). So that is your answer.
Circumference= pi × d
So
d= circumference/pi
So to find out the diameter, just do 56.52/pi= 17.99mm (2 d.p.)
Answer:
see explanation
Step-by-step explanation:
Using the tangent ratio in the right triangle
tan A =
=
=
, then
∠ A =
(
) ≈ 41° ( to the nearest degree )
The sum of the angles in the triangle = 180° , then
∠ B + 41° + 90° = 180°
∠ B + 131° = 180° ( subtract 131° from both sides )
∠ B = 49°
Using Pythagoras' identity in the right triangle
AB² = BC² + AC² = 7² + 8² = 49 + 64 = 113 ( take square root of both sides )
AB =
≈ 10.6 ( to the nearest tenth )