+0  
 
-1
230
1
avatar+3027 

Help.

NotSoSmart  Nov 17, 2017
 #1
avatar
+1

Solve for x:
2 x^2 - 3 x + 2 = 0

Divide both sides by 2:
x^2 - (3 x)/2 + 1 = 0

 

Subtract 1 from both sides:
x^2 - (3 x)/2 = -1

 

Add 9/16 to both sides:
x^2 - (3 x)/2 + 9/16 = -7/16

 

Write the left hand side as a square:
(x - 3/4)^2 = -7/16

 

Take the square root of both sides:
x - 3/4 = (i sqrt(7))/4 or x - 3/4 = 1/4 (-i) sqrt(7)

Add 3/4 to both sides:


x = 3/4 + (i sqrt(7))/4 or x - 3/4 = 1/4 (-i) sqrt(7)

Add 3/4 to both sides:


x = 3/4 + (i sqrt(7))/4        or           x= 3/4 - (i sqrt(7))/4

 

 

Solve for x:
x^2 - 4 x - 5 = 0

 

The left hand side factors into a product with two terms:
(x - 5) (x + 1) = 0

 

Split into two equations:
x - 5 = 0 or x + 1 = 0

 

Add 5 to both sides:
x = 5 or x + 1 = 0

 

Subtract 1 from both sides:
x = 5                or                x = -1

Guest Nov 17, 2017
edited by Guest  Nov 17, 2017

8 Online Users

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.