Answer: 38.5 cm^2
Step-by-step explanation:
Length of wire = 7*2 + 4*2 = 22 cm
Radius of Circle = 22/(2pi) = 3.5 cm
Area of Circle = (3.5)^2*pi = 38.5 cm^2
Answer:
C. x=4
Step-by-step explanation:
4x + 7y = 1 ⇒ 12x + 21y = 3
3x + 10y = 15 ⇒ <u>12x + 40y = 60</u>
<u>-19y</u> = <u>-57</u>
-19 -19
y = 3
4x + 7(3) = 1
4x + 21 = 1
<u> - 21 - 21</u>
<u>4x</u> = <u>-20</u>
4 4
x = -5
(x, y) = (-5, 3)
Answer:
Step-by-step explanation:
Time = distance/speed
Considering the first stage,
Speed = 20km/hr
Distance = 5km
Time = 5/20 = 0.25 hour
Considering the second stage,
Speed = 10km/hr
Distance = 5km
Time = 5/10 = 0.5 hour
Considering the third stage,
Speed = 25km/hr
Distance = 5km
Time = 5/25 = 0.2 hour
Considering the third stage,
Speed = 20km/hr
Distance = 5km
Time = 5/20 = 0.25 hour
Therefore, the time it took the biker to complete the race is
0.25 + 0.5 + 0.2 + 0.25 = 1.2 hours
