Answer:
the first answer or a
Step-by-step explanation:
just believe meeeee
Answer:
x-int (6.2, 0)
y-int (0, 3.1)
Step-by-step explanation:
x-intercept is found when y = 0.
y-intercept is found when x = 0.
Step 1: Define equation
2x + 4y = 12.4
Step 2: Find x-intercept
<em>Substitute y for 0.</em>
2x + 4(0) = 12.4
2x = 12.4
x = 6.2
(6.2, 0)
Step 3: Find y-intercept
<em>Substitute x for 0.</em>
2(0) + 4y = 12.4
4y = 12.4
y = 3.1
(0, 3.1)
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.)
13h and 5min. Hope this helps:)
5x-9y=-65
10x-3y=20
Multiple the first equation by 2
10x-18y=-130
10x -3y=20
Then subtract the two equations to get rid of the x
21y=-150
Divide the -150 by 21
Y=-7.14
Plug the y into the original equation. (Either one)
5x-9(-7.14)=-65
5x-64.28=-65
Then add 64.28 to the -65
5x=-0.72
Divide by 5
X=-0.144
I hope this is right
