5m+2(m+8)+3
5m+2m+16+3
7m+19
#1. x = - (2y) / (1-y)
#2. x = (-4y-3)/(1-y)
I can't really see the other questions, so I only did the first two. Hope this helps!
Given:
- Bought n items of product A at 1/5 rs each
- bought n items of product B at 1/4 rs each
He mixed the two items and sold each at 2/9 rs each.
He lost 3 rs in the above batch of articles.
Solution:
revenue = 2n* (2/9) rs = 4n/9 rs
cost = n/5+n/4 rs = n(1/5+1/4)
Profit = revenue-cost = 4n/9-n(1/5+1/4) = -3 rs
Solve for n
4n/9-n(1/5+1/4) = -3
factor out n
n(4/9-1/5-1/4)=-3
n(80-36-45)/180=-3
-n/180=-3
n=3*180=540
Total number of products bought
= n+n = 540+540 = 1080
9 more than y is an expression so it would be 9+y
We are told that f(1) = -1.5, and that f(n+1) = -2f(n).
Then: f(2) = -2f(1) = -2(-1.5) = +3 (answer)
