Answer:
see explanation
Step-by-step explanation:
note when x = - 3
(- 3)³ + 2(- 3)² + 4(- 3) + 21 = - 27 + 18 - 12 + 21 = 0
hence x = - 3 is a zero and (x + 3) is a factor and dividing gives
= (x + 3)(x² - x + 7)
For zeros equate to zero
(x + 3)(x² - x + 7) = 0
equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x² - x + 7 = 0 ← solve using quadratic formula
x = (1 ± ) / 2 = (1 ± 3i
) / 2
x = ±
zeros are x = - 3, x = ±
Answer:
88/7 ft = 12.6 ft (nearest tenth)
Step-by-step explanation:
Circumference of a circle = 2r
<u>Radius of inner circle</u>
Given:
⇒ 22 = 2 x (22/7) x r
⇒ r = 3.5
So the radius of the inner circle is 3.5 ft
<u>Radius of outer circle</u>
If the distance between the inner circle and the outer circle is 2 ft, then the radius of the outer circle = 3.5 + 2 = 5.5
<u>Circumference of outer circle</u>
Therefore, circumference of outer circle:
= 2 x (22/7) x 5.5
= 242/7 ft
<u>Difference between circumferences</u>
Difference = outer circle circumference - inner circle circumference
= 242/7 - 22
= 88/7 ft
= 12.6 ft (nearest tenth)