4(-2)-3 = -8-3 = -11
Answer: -11
<span>[ (1 / 36) - (1 / x²) ] / [ (1 / 6) + (1 / x) ]
[ (x² - 36) / 36x² ] / [ (x + 6) / 6x ]
</span>remember that<span>:
x² - 36 = (x + 6)(x - 6)
so
[ (x+6)(x-6) / 36x² ] / [ (x + 6) / 6x ]
[ (x+6)(x-6) / 36x² ] * [ 6x / (x + 6) ]
6x / 36x² = 1 / 6x
[ (x+6)(x-6) / 6x ] * [ 1 / (x+6) ] -------------------- > </span>(x - 6) / 6x<span>
The answer is </span>(x - 6) / 6x<span>
</span>
I think it is a but I’m not sure
Answer:
It takes 26 2/3 gallons to make a 400 mile trip.
Step-by-step explanation:
This question is simply asking for the number of miles per gallon . In math, <em>per</em> means this is meant to be written as a fraction.
"If a trip of 270 miles required 18 gallons of gas" is actually saying "270 miles per 18 gallons." This can be written as a fraction like so: 270/18.
If we're looking for the amount of gas used for a 400 mile trip, we have the fraction: 400/g, g being the amount of gallons it took to make that trip.
Now we can set up the proportion: 
Cross multiply and solve accordingly.

400
/g
So the answer is:
It takes 26 2/3 gallons to make a 400 mile trip.