Answer: 8
Step-by-step explanation:
Since AB is a tangent, angle CAB is a right angle. Thus, by the Pythagorean theorem, 
9514 1404 393
Answer:
A. 53.5cm^2
Step-by-step explanation:
The area of the circle is ...
A = πr²
A = 3.14(5 cm)² = 78.5 cm²
The area of the triangle is ...
A = 1/2bh
A = 1/2(10 cm)(5 cm) = 25 cm²
The shaded area is the difference between the circle area and the triangle area:
shaded = 78.5 cm² -25 cm² = 53.5 cm²
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<em>Additional comment</em>
As with many multiple-choice questions, you can simply pick the answer that is not outlandish. The circle will fit into a square that is 10 cm on a side, so its total area is less than 100 cm² (eliminates choice B).
The shaded area is definitely more than 1/4 of that 100 cm² square, so choices C and D are eliminated, too. The only choice that is not unreasonable is choice A.
Answer:
40 degrees
Step-by-step explanation:
The sum of the angles is 180.
A 100 degree angle cannot be a base angle because then
the sum of the base angles would be 200 degrees.
The 100 must be the vertex angle.
Equation:
x + x + 100 = 180
2x = 80
x = 40 degrees.
Each of the base angles is 40 degrees.
