Final answer:
When a = 2 and b = -1, the value of the expression 2a² - 3b is 11.
Step-by-step explanation:
To find the value of this expression, substitute the given values of a and b into the expression. So when a = 2 and b = -1, we have:
2(2)² - 3(-1) = 2(4) + 3 = 8 + 3 = 11
Therefore, the value of the expression 2a² - 3b when a = 2 and b = -1 is 11.
Learn more about Evaluating expressions