Answer: The equations are
6x - 6y = 9
4x + 4y = 9
Step-by-step explanation:
Let x represent the speed of the row boat in still water.
Let y represent the speed of the current.
Dana can travel 9 miles in her rowboat in 6 hours against the current. This means that the total speed at which she travelled is
(x - y) miles per hour.
Distance = speed × time
Distance travelled against the current is expressed as
9 = 6(x - y)
6x - 6y = 9
With the current, it takes 4 hours to row the same distance. This means that the total speed at which she travelled is
(x + y) miles per hour.
Distance travelled with the current is expressed as
9 = 4(x + y)
4x + 4y = 9
Answer:
24
Step-by-step explanation:
area of circle = πr²
πr² = 144π
Cancel out π
r² = 144
r = √144
r = 12
diameter = 2 x radius
diameter = 2 x 12
diameter = 24m
* diameter is the "width of a circle", the distance from the widest points of the circle
Answer: the charge would be the same after 5 miles
Step-by-step explanation:
Let x represent the distance at which both companies charge the same amount.
company A charges a flat fee of four dollars plus 2 dollars per mile. It means that the total charge for x miles would be
4 + 2x
Company B does not charge a flat fee but charges $2.80 per mile driven. It means that the total charge for x miles would be 2.8x.
For the charge to be the same, the number of miles would be
2.8x = 4 + 2x
2.8x - 2x = 4
0.8x = 4
x = 4/0.8
x = 5
Answer:
$85
Step-by-step explanation:
$35 + $1 x 50 guests = $85
