A:
(f+g)(x)=f(x)+g(x)
(f+g)(x)=4x-5+3x+9
(f+g)(x)=7x+4
B:
(f•g)(x)=f(x)•g(x)
(f•g)(x)=(4x-5)(3x+9)
(f•g)(x)=12x^2-15x+36x-45
(f•g)(x)=12x^2+21x-45
C:
(f○g)(x)=f(g(x))
(f○g)(x)=4(3x+9)-5
(f○g)(x)=12x+36-5
(f○g)(x)=12x+31
True
Every function is a relation, but not every relation is a function.
Hope this helps :)
First let's get rid of the x by multiplying the tip equation by -2
-2 (-6x - 2y = -4)
+
(-12x - 5y = -13)
Distribute
(12x + 4y = 8)
+
(-12x - 5y = -13)
x cancels out and you're left with
-1y = -5
y = 5
Now solving for x, plug in your y into one of the equations
-6x - 2(5) = -4
-6x - 10 = -4
-6x = 6
x = -1
(-1 , 5) is the solution
