Answer:
m and n are just labels. They don't really mean anything. In this situation m is used as a general label to be summed over, and n is for a specific term in the sum. They're written differently, because that way you can write things like Which is how we come to the second and third equation you list in your post.
Step-by-step explanation:
Rewrite (1st) equation
-x - 2y = - 9
multiply the (1st) equation by 3
-3x - 6y = -27
now you have
-3x - 6y = -27
3x - 6y = -15
-----------------------add
-12y = -42
y = 3.5
2(3.5) = -x + 9
7 = - x + 9
x = 2
answer
(2 , 3.5)
Answer:
1.2.05 2.0.919 3 sf
Step-by-step explanation:
1. cos 70=x/6
6 cos 70=x
x=2.05
2.cos 45=x/1.3
1.3 cos 45=x
x=0.919
3.cant see ;-;
Answer:
the middle is zero count up the lines
Step-by-step explanation:
this looks complicated, that's my best guess
Answer:
It costs $42.43
Step-by-step explanation:
Lets explain how to solve the problem
- The cost of 
kilogram of candy is $7.5
- We need to find the cost of 
kilogram
We can use the ratio to find the answer
======= Dollar : Kilogram
======= 7.5 :
======= c :
By using cross multiplication
∴ c × = 7.5 ×
∵ = 
∴ = 
∴ c × = 7.5 ×
∴ c × = 
Divide both sides by
∴ c = ÷
Change the division sign to multiplication sign and reciprocal the
fraction after the division sign
∴ c = × 
∴ c = 
= 42.43 dollars
∵ c represents the cost of kg
∴ It costs $42.43
