Let n = cost of 1 notebook
Let p = cost of 1 pencil
Then,
3n + 4p = 8.5
5n + 8p = 14.5
You can solve for one variable in terms of the other and then substitute into the remaining equation.
3n + 4p = 8.5
+ 5n + 8p = 14.5
Multiply the top equation by -2 so that the p-containing terms cancel each other out:
-2(3n + 4p = 8.5)
+ 5n + 8p = 14.5
-n + 0 = -2.5
So after dividing both sides by -1, we see that n = $2.5. Plugging into the first equation gives p = $0.25.
3n + 4p = 8.5
5n + 8p = 14.5
Answer:
f = 4
Step-by-step explanation:
60= 15f
divide both side by 15
f = 4
From the following choices, the correct step in evaluating: ∫ cos2 5x dx is 1 - cos 10x / 2dx.
I believe the answer will be 23in
Diagonals are = n - 2
Interior = 144
Exterior angle = 180 - 144 = 36
Formula for exterior of a regular polygon given the number of sides:
= 360/n
36 = 360/n
n = 360/36 = 10
n = 10
Number of diagonals = n - 2 = 10 - 2 = 8
8 diagonals.