+0  
 
0
275
3
avatar+1442 

I think I complete the square but idk Rewrite the expression $4s^2 + 28s + 45$ in the form $(cs + p)^2 + q$. What is $q$?

AnonymousConfusedGuy  Oct 20, 2017
 #1
avatar+88848 
+2

4s^2 + 28s + 45    factor out  the 4

 

4 [ s^2  + 7s  +  45/4]

 

Take (1/2) of 7  = 7/2......square this = 49/4  ....add it and subtract it

 

4 [ s^2 + 7s + 49/4 + 45/4 - 49/4 ] 

 

Factor the first three terms and simplify

 

4 [  ( s + 7/2)^2  - 1 ]

 

4(s + 7/2)^2  - 4

 

So q =  -4

 

 

cool cool cool

CPhill  Oct 20, 2017
 #2
avatar
0

CPhill: Aren't you actually dividing by 4 in the first step and it should disappear altogether in the 2nd step (outside the bracket)?

Guest Oct 20, 2017
 #3
avatar+88848 
0

 

This would be true if we were setting the equation to 0  and solving

 

But we aren't solving anything here......we are just completing the square

 

 

cool cool cool

CPhill  Oct 20, 2017

45 Online Users

avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.