Question

Solve the following quadratic equations by completing square :

2y2 + 5y + 1 = 0

Answer 1

Hey !!
Given Expression -
2y²+5y+1=0

(√2y)²+2(√2y)(5/2√2)+(5/2√2)²-(5/2√2)²+1

[√2y+5/2√2]² = (5/2√2)²-1

[√2y+5/2√2]² = 25/8 - 1

[√2y+5/2√2]² = 17/8

[√2y+5/2√2] = ±√17/2√2

Case 1 -
[√2y+5/2√2] = +√17/2√2

y=√17-5/4 Ans.

Case 2 -
[√2y+5/2√2] = -√17/2√2

y=√17+5/4 Ans.

Hope it helps :)