What is the missing coefficient in the equation given that p(2) = 128?

Question

What is the missing coefficient in the equation given that p(2) = 128?

 

p(x)= ____________ x^5

 

Answer 1

Makayla, I promise this isn't as bad as it looks!

 

Remember that f(2) means we are going to plug in 2 for every x. This gives us       2⁵.

 

Since 2⁵ is 32, then what do we need to multiply 32 by to get 128? 4, right?

 

Let's check. f(x) = 4x⁵

f(2) = 4(2⁵) = 4(32) = 128. Check!

 

Hope this helps!

Answer 2

p(2) means p for x=2.  With x=2, you really only need to calculate 2⁵, which is 2*2*2*2*2, or 32. Now we have 128=__32.  To solve this, reverse the problem to 128/32, which is 4. Your missing coefficient is 4.