Answer:
Exact area: 39.2π cm²
Approximate area: 123.2 cm²
Step-by-step explanation:
The area of a circle is πr².
A full circle can be thought of as a sector of a circle with 360° of central angle. For a sector of a circle with a central angle of n°, multiply the area of the circle by the fraction n°/360°.
The formula for the area of a sector of circle with central angle n° and radius r is
A = (n°)/(360°) × πr²
Here we have n = 72; r = 14 cm
A = (n°)/(360°) × πr²
A = (72°)/(360°) × π × (14 cm)²
A = 39.2π cm² = 123.2 cm²
Answer:
y
Step-by-step explanation:
First you would find y because two or more of the numbers have it. Then you would be able to solve for x
Answer:
h = 14
Step-by-step explanation:
-98 = -7h
/-7 /-7
14 = h
Answer: A, B, C, and E
Step-by-step explanation:
If both sides are real numbers, then the product will be a real number.
If in at least one of the sides we have a complex number, then the product will be real if:
The other number is zero.
The other number is the conjugate of the first.
This is when:
Suppose we have a number:
z = a + b*i
The conjugate will be:
w = a - b*i
And the product between them is:
(a + b*i)*(a - b*i) = a^2 + a*b*i - a*b*i + b^2 = a^2 + b^2
Then the options that will have a real answer are:
A. (4+5i)(4-5i) = 4^2 + 5^2 = 16 + 25 = 41
B. (4 + 91)*(41 - 9) = 3040
C. (3 + 2*i)*(3 -2*i) = 3^2 + 2^2 = 9 + 4 = 13
E. (312 + 7i)*(312 - 7i) = 312^2 + 7^2 = 97,393
Nanometer, micrometer, millimeter, centimeter, decimeter, meter, kilometer
