Answer:
Step-by-step explanation:
You do not need to where the formula comes from but, just for fun, here’s a hint
To add up the numbers 1 to 10
Write out the numbers
1 2 3 4 5 6 7 8 9 10
Write them backwards
10 9 8 7 6 5 4 3 2 1
Add up both lists
11 11 11 11 11 11 11 11 11 11
This is 10 × 11 = 110
But this is twice the sum as two lots were added together
So the sum of the numbers 1 to 10 is 110 ÷ 2 = 55
ArSeqSum Notes fig4, downloadable IGCSE & GCSE Maths revision notes
Olga worked 37.5 hours last week and earned $12.50 an hour.
[ h = the number of hours y = total earnings ]
12.50h = y
12.50(37.5) = y
468.75 = y
She earned $468.75 last week
If she gets a $2.50 per hour raise:
12.50 + 2.50 = 15.00
She gets $15 per hour.
How many hours will she have to work to make $468.75?
15h = 468.75 Divide 15 on both sides to get "h" by itself
h = 31.25
She needs to work 31.25 hours
Answer: (3, -3)
Step-by-step explanation:
You substitute each point into the function and see if it fits:
(-2, -1) ⇒ -2(-2) + 3 = 4 + 3 = 7 ≠ -1
(3, -3) ⇒ -2(3) + 3 = -6 + 3 = -3
(3, 3) ⇒ -2(3) + 3 = -6 + 3 = -3 ≠ 3
(-3, -9) ⇒ -2(-3) + 3 = 6 + 3 = 9 ≠ -9
Answer:
\\x= P/(c -d)[/tex],
Assume that the price of each minute in the first plan is $c and that the second plan charges a flat rate of $P and a charge of additional $d for every minute.
Step-by-step explanation
Assume that the price of each minute in the first plan is $c and that the second plan charges a flat rate of $P and a charge of additional $d for every minute.
Thus, the monthly cost of a customer who consumes x minutes in each plan is:
For the first plan: 
and for the second plan: 
Considering that the monthly costs must be the same in each plan, you have to:
![cx = P + dx\\ transposing terms\\cx - dx = P\\ applying common factor\\(c -d)x = P\\ dividing by [tex]c - d](https://tex.z-dn.net/?f=cx%20%3D%20P%20%2B%20dx%5C%5C%20transposing%20terms%3C%2Fp%3E%3Cp%3E%5C%5Ccx%20-%20dx%20%3D%20P%5C%5C%20%20%20applying%20common%20factor%3C%2Fp%3E%3Cp%3E%5C%5C%28c%20-d%29x%20%3D%20P%5C%5C%20dividing%20by%20%5Btex%5Dc%20-%20d)
\\x= P/(c -d)[/tex].
For example if 
, Then the number of minutes would be, 
and the total cost for each plan would be 
