Answer:
B. s = 0.85r
Step-by-step explanation:
The sale price is 15% off the regular price. In equation form, that is ...
s = r - 15%×r
s = r(1 - 0.15) = 0.85r
The equation that can be used to calculate the sale price is <em>s = 0.85r</em>.
Answer:
sandwich = 6.50
Step-by-step explanation:
Let s = sandwich price
d = drink price
6s + 4d = 53
4s + 6d = 47
Multiply the first equation by 3
18s + 12d = 159
Multiply the second equation by -2
-4s - 12d = -94
Add these equations together
18s + 12d = 159
-8s - 12d = -94
--------------------------
10s = 65
Divide by 10
s = 65/10
s =6.5
<h3>
Answer: (n-1)^2</h3>
This is because we have a list of perfect squares 0,1,4,9,...
We use n-1 in place of n because we're shifting things one spot to the left, since we start at 0 instead of 1.
In other words, if the answer was n^2, then the first term would be 1^2 = 1, the second term would be 2^2 = 4, and so on. But again, we started with 0^2 = 0, so that's why we need the n-1 shift.
You can confirm this is the case by plugging n = 1 into (n-1)^2 and you should find the result is 0^2 = 0. Similarly, if you tried n = 2, you should get 1^2 = 1, and so on. It appears you already wrote the answer when you wrote "Mark Scheme".
All of this only applies to sequence A.
side note: n is some positive whole number.
