An easy question all wrong or or no-work answers will be reported.

y=1/2x-6
2x+6y=19

solve using two different methods(substitution/elimination) and explain which method you found to be more efficient.

Substitution:
2x + (6(1/2x - 6)) = 19
2x + 3x - 36 = 19
5x - 36 = 19
+ 36
5x = 55
÷ 5
x = 11

y = (1/2 × 11) - 6
y = 5.5 - 6
y = -0.5

Elimination:
y = 1/2x - 6
- y
0 = 1/2x - 6 - y
+ 6
1/2x - y = 6

3x - 6y = 36
2x + 6y = 19
(add)
5x = 55
÷ 5
x = 11

y = (1/2 × 11) - 6
y = 5.5 - 6
y = -0.5

I hope this helps! Let me know if you need me to explain why I did some things :)

The first one is correct