Answer:
The labor fee is $14.25, each quart of oil costs $2.25.
Step-by-step explanation:
Let $x be thee price of each quart of oil and $y be a flat fee for labor.
1. If the oil change for one car required 5 quarts of oil, then these 5 quarts cost $5x and together with a flat fee for labor it cost $25.50. Thus,
5x+y=25.50.
2. If the oil change for another car required 7 quarts of oil, then these 7 quarts cost $7x and together with a flat fee for labor it cost $30.00. Thus,
7x+y=30.00.
3. Subtract from the second equation the first one, then
Substitute it into the first equation:
The labor fee is $14.25, each quart of oil costs $2.25.
Here the denominators are quadratics , so we need to factorise them first
1/(x²-5x) +3/(x²+2x-35)
factorising x²-5x ,
here GCF is x, so taking x out we have
x(x-5)
factorising x²+2x-35 using AC method,
we find factors of -35 that add up to give 2
(x-5)(x+7)
Since we have x-5 common in both denominators, so lcd of the rational expression will be product of x(x-5)(x+7)
lcd is x(x-5)(x+7)
Okay, as you know, adding a positive and a positive gives you a bigger positive number. e.g 21 + 19 = 40.
Subtracting a positive from a positive might give you a negative number or a smaller positive number. e.g 21 - 19 = 2 or 20 - 24 = -4. That's simple, we all learned this! :)
Adding two negatives (e.g -4 + -5) will always give you a negative number. To make it easier, just think of the numbers only (4, 5), add them together, and then just put a negative sign by the answer (e.g 4 + 5 = 9 so put - to make -9).
Subtracting two negatives can be a bit tricky! When we say, for example, -5 - -4, we must turn the negative number that was to the right of the minus ( -4) into a positive number! So now it becomes -5 +4 ! And then you get your answer. (which is -1).
Adding a positive to a negative can give you a positive or a negative answer. It just depends which number is "bigger". E.g -20 + 31. << 31 is the "bigger" number, and it is a positive, so we know that our answer will be positive. E.g -20 + 9. << 20 is the "bigger" number (even though it's a negative but forget about that) and it is negative, so we know that our answer will be negative.
Adding a negative to a positive can give you a negative or a positive answer. Like I said, it depends on which number is "bigger". e.g 20 + -9 . We can just remove the + sign and it now becomes 20 -9, which is easier to understand. 20 is the bigger number, and it is positive, so we get a positive answer. e.g 20 + -30 becomes 20 -30 and -30 is the "bigger" number and it is negative, so we'll get a negative answer.
Subtracting a negative from a positive does the thing I mentioned earlier: e.g 20 - -9. The -9 is right of the minus sign and becomes positive: 20 +9! :)
Subtracting a positive from a negative, like I said, depends on which number is "bigger". e.g -30 - 9 (we know 9 is positive even though we don't show the + sign). Now, to make it simple, just block out the - sign by the 30 so it becomes 30 - 9. You know what that answer is: 21. But because -30 is "bigger", and it is a negative number, the answer will be negative so it's -21. E.g -30 - 42 << Block out the - sign by the 30, and 42 is the "bigger" number, so the answer will be a positive. Just look at the difference between "bigger" number and the smaller number (without signs) . That'll give your answer. 42 - 30 = 12. 42 was the "bigger" number and a positive, and we looked at the difference. :)
Answer: 8x−3
Step-by-step explanation:
Let's simplify step-by-step.
7−x−−5x−10+4x
=7+−x+5x+−10+4x
Combine Like Terms:
=7+−x+5x+−10+4x
=(−x+5x+4x)+(7+−10)
=8x+−3
If I Helped, Please Mark Me As Brainliest, Have A Great Day :D
