+0  
 
0
593
1
avatar

solve the equation 4x(x-2)=7 using uadratics

 Jan 5, 2015

Best Answer 

 #1
avatar+111329 
+5

4x(x-2)=7     let's put this in standard form

4x^2 - 8x - 7 = 0      now, using a =4, b = -8 and c = -7, we have...

x = ( -b ±√ [b^2 - 4ac] ) / 2a

x =  ( 8 ±√ [64 - 4(4)(-7)] ) / 8

x = (8±√ [176]) / 8

x = [8 ±√(16*11)] / 8

x = [ 8 ± 4√11] / 8      ( divide everything by 4 )

x = [2 ± √11] / 2

 

  

 Jan 5, 2015
 #1
avatar+111329 
+5
Best Answer

4x(x-2)=7     let's put this in standard form

4x^2 - 8x - 7 = 0      now, using a =4, b = -8 and c = -7, we have...

x = ( -b ±√ [b^2 - 4ac] ) / 2a

x =  ( 8 ±√ [64 - 4(4)(-7)] ) / 8

x = (8±√ [176]) / 8

x = [8 ±√(16*11)] / 8

x = [ 8 ± 4√11] / 8      ( divide everything by 4 )

x = [2 ± √11] / 2

 

  

CPhill Jan 5, 2015

13 Online Users

avatar
avatar
avatar