The minimum distance will be along a perpendicular line to the river that passes through the point (7,5)
4x+3y=12
3y=-4x+12
y=-4x/3+12/3
So a line perpendicular to the bank will be:
y=3x/4+b, and we need it to pass through (7,5) so
5=3(7)/4+b
5=21/4+b
20/4-21/4=b
-1/4=b so the perpendicular line is:
y=3x/4-1/4
So now we want to know the point where this perpendicular line meets with the river bank. When it does y=y so we can say:
(3x-1)/4=(-4x+12)/3 cross multiply
3(3x-1)=4(-4x+12)
9x-3=-16x+48
25x=51
x=51/25
x=2.04
y=(3x-1)/4
y=(3*2.04-1)/4
y=1.28
So now that we know the point on the river that is closest to Avery we can calculate his distance from that point...
d^2=(x2-x1)^2+(y2-y1)^2
d^2=(7-2.04)^2+(5-1.28)^2
d^2=38.44
d=√38.44
d=6.2 units
Since he can run at 10 uph...
t=d/v
t=6.2/10
t=0.62 hours (37 min 12 sec)
So it will take him 0.62 hours or 37 minutes and 12 seconds for him to reach the river.
P = w * .6
Explanation: First, we must determine the price per pound of watermelon. To do this, we take the cost of the watermelons, and divide it by the number of pounds. 4.38 / 7.3, which is .6. This tells us each pound costs 60 cents, or $.6. We’re trying to say “The total price of watermelon would be the amount of watermelon bought times .6.” Plug in the variables you’re given, and you get p = w * 6.
Answer:
X = 1
Step-by-step explanation:
subtract 14 from both sides
6x = 6
divide both sides by 7
X = 1
Answer:
f = .39
Step-by-step explanation:
d (v) = 2.15 v^2 / (64.4 f)
v = 40
d = 138
substitute these in
138 = 2.15 (40)^2 / (64.4 *f)
simplify
138 = 2.15 (*1600) / (64.4 *f)
138 = 3440 / (64.4 *f)
multiply each side by 64.4f
138 * 64.4 f = 3440
8887.2 f = 3440
divide by 8887.2
8887.2 f /8887.2= 3440/8887.2
f=.38707
to the nearest hundredth
f = .39
Answer:
x=41
y=139
Step-by-step explanation:
x+y = 180 since they form a straight line
y is 3x +16
y = 3x +16
Replace y in the first equation
x+3x +16 = 180
Combine like terms
4x +16 = 180
Subtract 16 from each side
4x+16-16 =180-16
4x =164
Divide each side by 4
4x/4 =164/4
x = 41
y = 3x +16
y = 3*41 +16 = 123+16 =139
