The answer that I got was 7
Answer:
8/7 min = 
Step-by-step explanation:
A rate 2 2/3 = 8/3 min per tank
B rate 2 min per tank
thus:
A rate = 3/8 tank per min
B rate = 1/2 tank per min
A+ B = 3/8 + 4/8 = 7/8 tank per min
7/8 x = 1
x = 8/7 min
Here's the rule for working with these things:
There are 3 signs associated with a fraction:
=> the sign of the numerator
=> the sign of the denominator
=> the sign of the whole fraction; (if the fraction were in
parentheses, this sign would be written outside).
-- You can change any 2 of them without changing the value of the fraction.
-- Changing any 1 of them changes the effective sign.
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Now, you said the fraction is negative.
So, let's start with the positive fraction, and see the different ways
that we could make it a negative fraction:
=> mark only the numerator negative
=> mark only the denominator negative
=> put parentheses around the fraction, and mark it negative outside
If you do any one of these things to a normal positive fraction,
it turns into a negative fraction.
Look at the choices you listed in the question:
-- in the numerator only ? Yes. That makes it a negative fraction.
-- in the denominator only ? Yes. That makes it a negative fraction.
-- both ? No. That makes it the same as a positive fraction.
-- put parentheses around the fraction, and a negative sign outside ?
Yes. This makes it a negative fraction.
-- it doesn't matter ? No. I hope you can see that it does matter.
Have I confused you ?
Is this more than you wanted to know ?
X2 + 12x +35 = 0
(x+5) (x+7) = 0
x + 5 = 0 x + 7 =0
x= - 5 or x= - 7
