Answer:
A = -81
B = 4/9
Step-by-step explanation:
An equation that has infinite solutions suggests that the left side equals the right side.
Expand brackets:
[tex]\dfrac23(12-Ax)-4 = 9(6 x + B)[/tex]
[tex]\implies 4-\dfrac23Ax = 54x+9B[/tex]
Equate coefficients of x:
[tex]\implies -\dfrac23A=54[/tex]
[tex]\implies A=-81[/tex]
Equate constants:
[tex]\implies 4=9B[/tex]
[tex]\implies B=\dfrac49[/tex]
