1st equation should be multiplied with 3
6x+9y=24
-6x+4y=11
________
13y=35
y=35/13
2x+3y=8...1
put y=35/13 in 1
2x+3(35/13)=8
26x+105=104
26x=-1
x=-1/26
You can only factor 
out of both terms:
Yes, it equals -1/6x + 10
You can use Pythagreos theorem to determine it!
Pythagreos theorem is a^2 + b^2 = c^2
1) 4^2 + 4^2 = 6^2
16 + 16 = 36
32 = 36 (So this is not a right-angled triangle )
2) 16^2 + 12^2 = 20^2
256 + 144 = 400
400 = 400 (Sp this is a right-ngled triangle)
