Hi there...
6 - y + 5y - 6y
Let's combine the like terms
(6)+(-y+5y-6y)
(6)+(-y-y)
(6)+(-2y)
6 - 2y
I hope that's help !
Together it would take a total of 4 hours to completely fill the pool.
1760 divided by 4 equals 440. This is the amount of liters that the second pump will fill the pool in 4 hours, so 440 divided by four is the amount that the second pump will fill the pool in one hour. 440/4= 110.
Now we add 110 to 330 to get the hourly rate of both pumps filling the pool. 110+330=440.
1760/440 equals 4.
So it takes 4 hours for both pumps to fill the pool.
Hope this helps!
Note
Tangents from an external point to a circle's circumference are equal.
So
WZ = WX
WZ = 5a + 12
WX = 7a + 5
7a + 5 = 5a + 12 Subtract 5 from both sides.
7a = 5a + 12 - 5
7a = 5a + 7 Subtract 5a from both sides.
7a - 5a = 7
2a = 7 Divide by 2
a = 7/2
a = 3.5
For this we first need to know how much watt hours are used in 12 house which we can find by taking 960/2=480 now we just need to take 960*4=3840 and add 480 which gives us are end answer of 4320 watt hours. Enjoy!=)