Answer:
y = m x + b equation of a straight line
m m' = -1 condition for perpendicular lines
If y = 4 x - 7 then m = 4 so m' = -.25
Y = -.25 X + A we need to find A
A = Y + .25 * 8 = 2 + 2 = 4
Y = -.25 X + 4
Check:
2 = -.25 * 8 + 4 = -2 + 4 = 2
It equals 8.4
Hope this answers ur question
Answer:
2 km/h
Step-by-step explanation:
Let x represent the speed of the river current, t₁ be the time spent rowing against the current and t₂ be the time spent rowing with the current.
Since the speed of the still water = 20 km/h.
The speed of rowing against the current = (20 - x)
The speed of rowing with the current = (20 + x)
We know that velocity = distance / time. Hence time = distance / velocity
t₁ = 36 / (20 - x)
t₂ = 22 / (20 + x)
but t₁ + t₂ = 3 hours
Therefore:
3 = 36 / (20 - x) + 22 / (20 + x)
multiply through by 400 - x²
3(400 - x²) = 36(20 + x) + 22(20 - x)
1200 - 3x² = 720 + 36x + 440 - 22x
3x² + 14x -40 = 0
This gives x = -6.7 or x = 2
x cannot be negative therefore x = 2 km/h
The speed of the river current is 2 km/h
Answer:
$2.95 for a small popcorn
Step-by-step explanation:
you do 8 multiplied by $7.50
which gives you $60 for the total spent together on tickets and then you do
$60 minus the total cost which is $83.60 and you get $23.60 left and then
you divide $23.60 by 8 because there is 8 people and you get a total of 2.96 for a popcorn
