X2+5x+y2-y=-2
X2+2*5x2+(5/2)^2-(5/2)^2+y2-2*y/2+(1/2)^2-(1/2)^2=-2
(x+5/2)^2+(y-1/2)^2-13/2=-2
(x+5/2)^2+(y-1/2)^2=9/2
So centre =(-5/2,1/2)
Radius=(9/2)^(1/2)
Answer:
-9xy+16x
Step-by-step explanation:
x(y-2) +3x(6-y) -7xy
Distribute
xy -2x +18x-3xy -7xy
Combine like terms
-9xy+16x
If x is the time, in hours, then:
x(55)=x(50)+15
5x=15
x=3 hours before Aisha is ahead of Luke
hope this helps you!
let
r--------> Alvin's average paddling rate in km/hour
y -------> speed of the current
in km/hour
we know that
speed= distance/time
------> solve for distance
distance=speed*time
to Campsite against the current
speed=r-y-----> speed=(r-3)
time=8 hours
distance=(r-3)*8------> equation 2
From Campsite with the current
speed=r+y-----> speed=(r+3)
time=3 hours
distance=(r+3)*3------> equation 1
equate equation 1 and equation 2-----> because is the same distance
(r+3)*3=(r-3)*8----> 3r+9=8r-24----> 8r-3r=24+9-----> 5r=33----> r=6.6 km/hour
therefore
the answer is
Alvin's average paddling rate is 6.6 km/hour
Answer:
d
Step-by-step explanation:
a is incorrect because
20/32=10/16=5/8
b is incorrect because
10/7=1.42 and 7/10=0.7 which don't equal each other
c is incorrect because
4/6 equals 2/3 not 3/5
d is correct because,
18/48=15/40
