wiz-icon
MyQuestionIcon
MyQuestionIcon
9
You visited us 9 times! Enjoying our articles? Unlock Full Access!
Question

Solve the equation 5x2– 6x– 2 = 0 by the method of completing the square. Find the positive root.


A

x= 3+195

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B

x= 3+175

No worries! We‘ve got your back. Try BYJU‘S free classes today!
C

x= 3195

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

x= 3+175

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A

x= 3+195


Multiplying the equation throughout by 5, we get

25 x2– 30 x – 10= 0

This is the same as

(5x)22×5x×3+323210=0

(5x3)2 - 9 - 10 = 0

(5x3)2 - 19 = 0

(5x3)2 = 19

5x - 3 = ±19

5x = 3±19

x = 3±195

Therefore, the roots are 3+195 and 3195.

Since 19>3, 3195 will be negative.

Thus, the positive root is 3+195.


flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Solving QE by Completing the Square
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon