Answer:
Speed of boat in still water = 11 miles per hour.
Step-by-step explanation:
Speed = distance / time
or
Distance= Speed * time
Let s be speed of the boat upstream and r be the speed of the river.
Then
Upstream speed= s- r = 60/6= 10 miles per hour
Downstream speed= s+r= 72/6= 12 miles per hour
Therefore
s-r= 10--------- equation A
s+r= 12--------- equation B
Adding equation A and Eq. b
s-r= 10--------- equation A
<u>s+r= 12--------- equation B </u>
<u>2s = 22 </u>
<u />
or
s= 22/2= 11 miles per hour.
Speed of boat in still water = 11 miles per hour.
Answer:
Step-by-step explanation:
(-3x + 2)(45x + 21) + (-4x + 25) = 50
-135x^2 - 63x + 90x + 42 - 4x + 25 = 50
-135x^2 + 23x + 67 = 50
-135x^2 + 23x + 67 - 50 = 0
-135x^2 + 23x + 17 = 0
quadratic formula : x = (-b ± √b^2 - 4ac)/2a
a = -135, b = 23, c = 17
x = -23 ± √23^2 - 4(-135)(17) / (2(-135)
x = (-23 ±√9709 )/ -270
x = 23/270 ± 1 / 270√9709/270
x = 0.4501 or x = - 0.2798 <=== these answers are rounded
Answer:
A
Step-by-step explanation:
3(x-2)
Replace x as 12
3(12-2)
3(10)
3 times 10
30
what are the measurments of the cone, but the formula to the cone is V
v = pi times radus times radius h/3