+0

# please help ! cphill- i saw that you've solved a problem similar to this, but w different numbers, can you or someone else help me w this :)

-3
88
8
+104

Find the number that can be placed in the empty space below so that the resulting quadratic is the square of a binomial:

x^2 + 22x + __

thanks !

Mar 20, 2020

#1
+1956
+3

Sorry I'm not CPhill.... but I'll try my best, too!

We know that in order to get a square of a binomial, we have to do (b/2)^2.

In this case, that will get us (22/2)^2 which is 121.

Therefore, we need to add 121 to each side, which will eventually get us (x+11)^2.

Hope this helped!

Mar 20, 2020
#2
+23566
+2

This is 'completing the square '  exercise'

take 1/2 of the 'x' coefficient     then square it    11^2 = 121

x^2 + 22x + 121    =    (x+11)2

Mar 20, 2020
#3
+104
0

hm.. neither of those answers are right.

Mar 20, 2020
#4
+23566
+2

The number to place in the blank is    '  121  '

ElectricPavlov  Mar 20, 2020
#5
+104
0

ohh! thank you EP:))

matthewmacdell  Mar 20, 2020
#6
+1956
+1

Yup! We're adding the 121 to each side, right?

CalTheGreat  Mar 21, 2020
#7
+109509
+1

Attn: CalTheGreat

There is only one side

This is NOT an equation.

All you are being asked is, 'what number do you need to add to   x^2 +22x    in order to make the expression a perfect square'.

the answer is   $$(\frac{22}{2})^2 = 11^2 = 121$$

$$x^2+22x+\boxed{121} = (x+11)^2$$

Melody  Mar 21, 2020
#8
+1956
+2

Melody, you're right! Thanks for correcting me!

CalTheGreat  Mar 21, 2020