9514 1404 393
Answer:
$2.50
Step-by-step explanation:
The question asks for the total cost of a notebook and pen together. We don't need to find their individual costs in order to answer the question.
Sometimes we get bored solving systems of equations in the usual ways. For this question, let's try this.
The first equation has one more notebook than pens. The second equation has 4 more notebooks than pens. If we subtract 4 times the first equation from the second, we should have equal numbers of notebooks and pens.
(8n +4p) -4(3n +2p) = (16.00) -4(6.50)
-4n -4p = -10.00 . . . . . . . . . . . simplify
n + p = -10.00/-4 = 2.50 . . . . divide by the coefficient of (n+p)
The total cost for one notebook and one pen is $2.50.
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<em>Additional comment</em>
The first equation has 1 more notebook than 2 (n+p) combinations, telling us that a notebook costs $6.50 -2(2.50) = $1.50. Then the pen is $2.50 -1.50 = $1.00.
One could solve for the costs of a notebook (n) and a pen (p) individually, then add them together to answer the question. We judge that to be more work.
Hello!
To solve this, first perform the opposite operation for the last operation (on the left side) on both sides. The last operation of the left side is squaring. Therefore, square root both sides.



Please note that you must include ±. This is because the square root of 64 can be either positive or negative, as a square of either a positive or negative number is positive.
Now, add 9 to both sides.

There are 2 solutions from here. One comes from adding 8, and the other subtracting 8. Therefore, the two solutions are:
y = 9 + 8 = 17
y = 9 - 8 = 1
Therefore, your two solutions are 17 and 1.
Hope this helps!
I think the rate is decreasing from:
(-infinity, ln9/3)