Question: -2a3  for a = 3

 

Step 1: Substitute 3 for a, because a = 3

 

-2(3)3

 

Step 2: Use order of operations. The order of operations calls for exponents before multiplying, so 3 to the third power is 27 (3 x 3 x 3 = 27)

The order of operations is:

              

Parenthesis

Exponents

Multiply

Divide

Add

Subtract

 

-2(27)

 

Step 3: Multiply –2 by 27. The answer is –54.

 

Answer: -54