Your answer is -B- i’m 100% sure
Answer:
3.14 ft
Step-by-step explanation:
The arc AB is the minor arc of the given circle. The length l of the minor arc of a circle is given as
l = Ф°/360° × 2πr
where
Ф is the angle of the arc at the center of the circle
r is the radius of the circle and
π is a mathematical constant equivalent to 22/7
r = 8/2 = 4 ft
Hence
l = 45°/360° × 2 × 22/7 × 4
= 22/7 ft
= 3.14 ft
9514 1404 393
Answer:
obtuse
Step-by-step explanation:
The law of cosines tells you ...
b² = a² +c² -2ac·cos(B)
Substituting for a²+c² using the given equation, we have ...
b² = b²·cos(B)² -2ac·cos(B)
We can subtract b² to get a quadratic in standard form for cos(B).
b²·cos(B)² -2ac·cos(B) -b² = 0
Solving this using the quadratic formula gives ...
The fraction ac/b² is always positive, so the term on the right (the square root) is always greater than 1. The value of cos(B) cannot be greater than 1, so the only viable value for cos(B) is ...
The value of the radical is necessarily greater than ac/b², so cos(B) is necessarily negative. When cos(B) < 0, B > 90°. The triangle is obtuse.
Answer:
19. 11
21. 119
Step-by-step explanation:
19.
(-5)² - [4(-3 ∙ 2 + 4)² + 3] + 5 =
= (-5)² - [4(-6 + 4)² + 3] + 5
= (-5)² - [4(-2)² + 3] + 5
= (-5)² - [4(4) + 3] + 5
= (-5)² - [16 + 3] + 5
= 25 - 19 + 5
= 6 + 5
= 11
21.
5 - 8[6 - (3 ∙ 2 - 8 + 2|4 ÷ -2 + (-3)| - 4) - 7 · 2] - 3² · (-2) =
= 5 - 8[6 - (3 ∙ 2 - 8 + 2|-2 + (-3)| - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - (3 ∙ 2 - 8 + 2|-5| - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - (3 ∙ 2 - 8 + 2(5) - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - (6 - 8 + 10 - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - (-2 + 10 - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - (8 - 4) - 7 · 2] - 3² · (-2)
= 5 - 8[6 - 4 - 7 · 2] - 3² · (-2)
= 5 - 8[6 - 4 - 14] - 3² · (-2)
= 5 - 8[2 - 14] - 3² · (-2)
= 5 - 8[-12] - 3² · (-2)
= 5 - (-96) - 9 · (-2)
= 5 + 96 + 18
= 101 + 18
= 119
