Answer:
In A and D the arrows are perpendicular, in B they are parallel and in C they are neither parallel nor perpendicular.
Step-by-step explanation:
Answer
Notebook each =$4
Folder each = $9
First we write out what we know
Notebook = n
Folder = f
It says a notebook is +5 than a folder so
f = n +5
It says he bought 3 notebooks and 2 folders for $30
3n + 2f = 30
Because we know from the first equation
f=n+5, we can substitute that into the second equation for f
3n + 2(n+5) = 30
3n + 2n +10 =30. Now Combine like terms
5n +10 =30. Now isolate n by subtracting 10 from both sides
5n = 20. Now isolate n by dividing both sides by 5
n = 4
Now we do the same thing to find f
We substitute the value of n (4) into the equation 3n + 2f =30
3(4) +2f =30
12 +2f =30. Now isolate f by subtracting 12 from both sides
2f = 18. Now isolate f by dividing both sides by 2
f = 9
We check our work by inserting the n and f values we found into one of the equations
n + 5 = f
4 + 5 = 9
9 = 9. It worked it equals so it’s correct
The number of positive roots is the number of changes of signs there are, then decrease by 2 each time and stop when you get to 1 or 0
negative roots, sub every x with -x and reevaluate, count change of signs
decrease by 2 each time and stop when you get to 1 or 0
y=+2x⁵-x⁴-2x³+4x²+x-2
+,-,-,+,+,-
1 2 3
3 or 1 positive roots
replace x with -x ( baically flip all signs of odd powerd numbers)
y=-2x⁵-x⁴+2x³+4x²-x-2
-,-,+,+,-,-
1 2
2 or 0 negative roots
3 or 1 positive roots
2 or 0 negative roots
2nd option is answer
So first you would divide 1950/6 to find the amount for one year of their age.
Then you would multiply that by the ages, which should get you 4 numbers, then you all those numbers together. Try 9750.
