The expression 2b to the third power + 5 evaluates to 255 when b is substituted with 5. The steps include cubing the number 5, multiplying the result by 2, and then adding 5.
To evaluate the expression 2b to the third power + 5 when b=5, we need to follow the order of operations, also known as PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction). First, we calculate the exponential part of the expression, which is b to the third power, or b cubed. Since b=5, we cube 5 to get 5³, which is 5 × 5 × 5 = 125. After finding the value of the exponential part, we multiply it by 2, then add 5 to get the final value.
Here's a step-by-step breakdown:
- Substitute the value of b into the expression: 2(5)³ + 5.
- Calculate 5³: 5 x 5 x 5 = 125.
- Multiply by 2: 2 × 125 = 250.
- Add 5: 250 + 5 = 255.
Therefore, the value of the expression when b=5 is 255.