Answer:
≈ 30.63 cm²
Step-by-step explanation:
The shaded area is calculated by subtracting the area of the inner circle from the area of the outer circle.
outer circle has radius = 8 ÷ 2 = 4 and inner circle has radius = 5 ÷ 2 = 2.5
shaded area = πr₁² - πr₂² (r₁ is outer and r₂ is inner )
A = π (4² - 2.5²)
= π(16 - 6.25) = 9.75π ≈ 30.63 cm²
Answer:
Step-by-step explanation:
For a triangle the area is

If our triangle is isosceles and the 2 congruent sides each measure 4 and they include an angle of 40 degrees, let's say that the vertex angle is 40 and the sides that are not the base each measure 4. If we drop an altitude from the vertex to the base, we cut the triangle into 2 right triangles, with the vertex angle being 20 degrees and the hypotenuse being 4. To find the base, then, which is opposite the angle, we use the sin ratio:
and
4sin(20) = b so
b = 1.368
But we need the whole base, and that is only half of it. So
2b = 2.736
To find the height, which is adjacent to the angle, we use the cos ratio:
and
4cos(20) = h so
h = 3.759
Now we have enough info to find the area of the triangle using the triangle area formula from above:
and
A = 5 meters squared.
Answer:
15 degrees Celsius
Step-by-step explanation:
Square Root to the Nearest Tenth
A B
33 5.7
34 5.8
35 5.9
36 6