Answer:
a=1.29 approx
Step-by-step explanation:
i think the answer is the second choice √9+√9=2√9
<em>Hoped this helped!</em>
9514 1404 393
Answer:
150 Wh
Step-by-step explanation:
We know the energy per bulb is 10 Wh per hour, so the total energy used by 3 bulbs in 5 hours is ...
(10 Wh/(bulb·hour))×(3 bulbs)×(5 hours) = 10·3·5 Wh = 150 Wh
Peter's account is 910-40x, and Marla's account is 470-2x. This is a system, so you must find the number that makes both equations end up with the same number. Basically trial and error. Here is what I did:
Let's try the number 10. 910-400=510 and 470-20=450. I need a higher number.
Let's try 13 next. 910-520=390 and 470-26=444. Now the number has to be lower.
Let's try 12. 910-480=430 and 470-24=446. Close, and a little lower.
11.5 is too low, and 11.7 is too high. 11.6 has Equation 1 at 446 and Equation 2 at 446.8. Very close!
It is somewhere around 11.6. I hope that this can give you a start in figuring it out, because I don't believe in giving the complete answer, because then you do not learn anything from it.
