I will give brainliest to whoever gets the right answer

Answer:
[tex]18[/tex]
Step-by-step explanation:
Step 1: Input the values and solve
[tex]b - 7a[/tex]
[tex](4) - 7(-2)[/tex]
[tex]4 - (-14)[/tex]
[tex]4 + 14[/tex]
[tex]18[/tex]
Answer: [tex]18[/tex]