Answer:
Below in bold.
Step-by-step explanation:
As its direct variation the graph is a straight line and passes through the origin (0,0) and the slope (y/x) is a constant.
The fraction (y/x) for any point will be a constant.
The fraction for (6, 4) is 4/6 = 2/3.
So also on the line we have:
(-9, -6) (because -6/-9 = 2/3).
and (3, 2).
Sorry if I get this wrong but if your trying to make a rectangle wouldn't it bc (-3,1) and (1,1)?
The Pythagorean theorem is a^2 + b^2 = c^2. You use it when solving for the sides of a triangle.
Yes
8+3= 11
You regroup the one
4+2=6+1=7
Hope this helps!
Let 
be the 20 marks of the boys, and 
be the 10 marks of the girls.
We know that the global mean was 70, meaning that
Multiplying both sides by 30 we deduce that the sum of the scores of the whole classroom is
By the same logic, we work with the marks of the boys alone: we know the average:
And we deduce the sum of the marks for the boys:
Which implies that the sum of the marks of the girls is 
And finally, the mean for the girls alone is
