ANSWER
22
EXPLANATION
Have to evaluate the expression,
[tex]2a+3b-bc[/tex]If the values of each constant are a = 3, b = 4, and c = -1, we just have to replace their values in the expression and solve,
[tex]2\times3+3\times4-4\times(-1)[/tex]First, solve the products and then add,
[tex]6+12+4=22[/tex]Hence, the answer is 22.