Steps:
1. Substitute the y in 4x + 10 with -5x-10
-5x-10= 4x + 10
2. Add 5x on both sides
-10= 9x + 10
3. Subtract 10 on both sides
-20= 9x
4. Divide by 9 on both sides
5. Your answer is
X= -20/9
Answer:
6 papayas and 11 pineapples
Step-by-step explanation:
So, we need to find an answer of how many papayas and pineapples she bought, and we only spent $48.
So, papayas are $2.50 each, and Pineapples are $3.00 each and we only bought 17 fruits total.
lets try 8 papayas, and 9 Pineapples.
$2.50 x 8 = $20.00 total on Papayas
$3.00 x 9 = $27.00 total on Pineapples.
That would only be $47 spent total.
Lets try 10 papayas and 7 pineapples.
$2.50 x 10 = $25.00
$3.00 x 7 = $21.00
That would only be a total of $26 spent.
Lets try 6 papayas and 11 pineapples.
$2.50 x 6 = $15.00
$3.00 x 11 = $33.00
This would be a total of $48 spent.
When
, we have


and of course 3 | 6. ("3 divides 6", in case the notation is unfamiliar.)
Suppose this is true for
, that

Now for
, we have

so we know the left side is at least divisible by
by our assumption.
It remains to show that

which is easily done with Fermat's little theorem. It says

where
is prime and
is any integer. Then for any positive integer
,

Furthermore,

which goes all the way down to

So, we find that

QED
When written in the
form, the slope of a line is given by the coefficient
. Moreover, two lines are parallel if the have the same slope.
Now, the slope of the known line is 4, so our line's slope will be four as well.
In general, when you know the slope
of a line and one of its points
, the equation of the line can be derived from the following formula:

Which in your case becomes

Expand the right hand side and solve for y:
