How to know that x=4 is not a solution to an equation? To verify this, we just evaluate the equation for x=4, to obtain a contradiction.
Let's do this for the first equation:
[tex]\begin{gathered} 2(4)+7=15, \\ 8+7=15, \\ 15=15. \end{gathered}[/tex]Here, we didn't get a contradiction (15 is equal to itself). This means that x=4 is indeed a solution to this equation.
Let's test the second one:
[tex]\begin{gathered} 3(4+1)=4+11, \\ 3\cdot5=15, \\ 15=15. \end{gathered}[/tex]As before, we have that x=4 is a solution.
Let's test the third one:
[tex]\begin{gathered} 4+5=3(4)-3, \\ 9=12-3, \\ 9=9. \end{gathered}[/tex]Again, x=4 is a solution.
Finally, let's verify the last one:
[tex]\begin{gathered} 4+12=5(4)-2, \\ 16=20-2, \\ 16=18. \end{gathered}[/tex]We got a contradiction! 16 is not equal to 18.
AnswerThe answer is the fourth option (equation).