CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Which constant must be added and subtracted to solve the quadratic equation 4x2+20x+92=0 by the method of completing the square?



A

25

loader
B

56

loader
C

23

loader
D

87

loader

Solution

The correct option is B

25


4x2+20x+92=0

Given equation is
(2x)2+(2x)(2)(5)+92=0
On putting 2x=y, we have y2+10y+92=0
y2+(2)5y+(5)2(5)2+92=0

(y+5)2=(5)292
(y+5)2=2592

Thus,25  must be added and subtracted to solve the given equation.


Mathematics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image