1. solve for x in first to just find nterms of y
x=12-y
sub that for x in other one
first divide that one by 2 to make it easier
2x-y=18
2(12-y)-y=18
24-2y-y=18
24-3y=18
minus 24 both sides
-3y=-6
divide -3
y=2
D is answer
2.
find intersection of x+y=5 and -2x+3y=6
or easiers, just test the intersections
wait, they all intersect in the same place
this is super easy
pick ANY point that is in that reigon and see if it is true
A, if we pick lets say (5,5)
that is false for x+y<5
not A
B
pick (10,0)
false for first one
not B
C
pick (0,0)
true for first
false for 2nd
not C
D. pick (-10,0)
true for first
true for 2nd
answer is D
answer is D for both questions
Factorial is the correct answer because in combinations the order does not matter
