Question

What is wrong with this question if K =4 then 3k+5=39

Answer 1

3k+5=-39

3(4)+5=-39
12+5=-39
17=-39

well 17 doesnt equal -39. the variable provided is wrong!

3k+5=-39
3k = -44
k = -14.66666667

so .... k should have been solved for instead of just plugging in a number!

Answer 2

You can tell it's wrong by plugging in 4 for K like so:
3(4) + 5 = 39

12 + 5 = 39

17 = 39

By looking at this you can tell it's false because 17 is not equal to 39.


I hope this helps! Feel free to let me know if you have any questions!

- mathwizzard3