Question

HELP!! 15 POINTS  Evaluate the expression when a = 4. 2a^3 A. 14 B. 24 C. 128 D. 512

Answer 1

2a^3 when a = 4:

First, to start out, our step should always be to substitute the value of the variable (a) into the problem. Below is what our new problem should look like with the value of the variable. Keep in mind that parentheses mean multiplication.
$2(4)^{3}$

Second, our next step is to simplify 4^3. Four raised to the third power equals 64, so 4^3 = 64. 
$2 \times 64$

Third, this last step is quite easy. All you need to do is (2 times 64). Best to use a calculator on this or take the hard way and do long multiplication. Either way, the answer for 2 times 64 is 128.

Answer: $\fbox {C: 128}$

Answer 2

C is the awseyto that pro