The general equation for any circle with its center at point (a, b) is
(x - a)² + (y - b)² = (radius)²
So the circle in the question is centered at (-3, -4), and its radius is 3 .
Answer:
ai) 73000 gal/yr
aii) $730 per year
b) 1000 days
Step-by-step explanation:
ai) The water usage per day is ...
(4 showers/day)(10 min/shower)(5 gal/min) = 200 gal/day
Then the usage per year is ...
(200 gal/day)(365 days/yr) = 73,000 gal/yr
__
aii) The cost of electricity is the cost of heating half the water usage, so is ...
(0.20 kWh/gal)(1/2)(73,000 gal/yr)($0.10/kWh) = $730/yr
__
b) The current daily cost of electricity for heating water is ...
($730/yr)/(365 days/yr) = $2/day
If the cost is cut in half, it will be $1 per day. That means the savings is $1 per day, so it will take 1000 days to recover the $1000 initial cost. (Effectively, the average cost for the first 1000 days is the same as if the water heater had not been replaced.)
Answer:
slope=2 and y intercept =1
Step-by-step explanation:
y=2x+1
y+2(0)+1
y=0+1
y=1
Answer:
C and E repr. constant functions.
Step-by-step explanation:
C and E represent constant functions. One can tell immediately by the fact that y remains the same even when x changes.
