Simplify this PLEASE

Answer:
[tex]\frac{12a-14b}{21}[/tex]
Step-by-step explanation:
Express the 2 fractions with a common denominator of 21
multiply numerator/denominator of first fraction by 3
multiply numerator/denominator of second fraction by 7
[tex]\frac{4a(3)}{7(3)}[/tex] - [tex]\frac{2b(7)}{3(7)}[/tex]
= [tex]\frac{12a}{21}[/tex] - [tex]\frac{14b}{21}[/tex]
= [tex]\frac{12a-14b}{21}[/tex]