Let
f(x)={2x+1if x≤3,8−4xif x>3.
Find the sum of all values of x such that f(x)=0.
I tried to do some guess and check (it worked on another problem i did similar to this) but it didn't really work...
When x <= 3,
f(x) = 0
2x + 1 = 0
x = -1/2
When x > 3,
8 - 4x = 0
x = 2
but x has to be greater than 3, so this is not actually a solution.
The sum of all values of x such that f(x) = 0 is -1/2.
Wow that was so fast thank you!
so we use algebra that there is no soluton for if x>3 and thre is one solution for x<=3 which is -1/2 since we get 2x=-1 and the only way for x>3 is 2 but 2 is not greater than 3 so it is -1/2+[nothing]=-1/2
+865 
