Answer: 7°
Explanation:
FBD = EBC
2x + 3 = 9x - 11
-7x = -14
x = -14/-7
x = 2
EBC = 9(2) - 11 = 18 - 11 = 7°

Let AB be a chord of the given circle with centre and radius 13 cm.
Then, OA = 13 cm and ab = 10 cm
From O, draw OL⊥ AB
We know that the perpendicular from the centre of a circle to a chord bisects the chord.
∴ AL = ½AB = (½ × 10)cm = 5 cm
From the right △OLA, we have
OA² = OL² + AL²
==> OL² = OA² – AL²
==> [(13)² – (5)²] cm² = 144cm²
==> OL = √144cm = 12 cm
Hence, the distance of the chord from the centre is 12 cm.
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<h2>
Hello!</h2>
The answer is:
The correct option is:
D. 40 feet.
<h2>
Why?</h2>
To solve the problem and calculate the width of the river, we need to assume that the distance from A to B and the angle formed between that distance and the distance from A to the other point (C) is equal to 90°, meaning that we are working with a right triangle, also, we need to use the given angle which is equal to 34°. So, to solve the problem we can use the following trigonometric relation:

Where,
alpha is the given angle, 34°
Adjacent is the distance from A to B, which is equal to 60 feet.
Opposite is the distance from A to C which is also equal to the width of the river.
So, substituting and calculating we have:


Hence, we have that the correct option is:
D. 40 feet.
Have a nice day!
Answer:
Factor: Something which is multiplied by something else. A factor can be a number, variable, term, or a longer expression. For example, the expression 7x(y+3) has three factors: 7 , x , and (y+3) .
10,11,15 is not right triangle
30,40,50 is right triangle
9,13,16 is not right angel
16,30,34 is right triangle