Respuesta :
If b^2 - 4ac is a perfect square, then the equation can be solved by factoring.
2x^2 + 7x + 3 = 0
a = 2, b = 7, c = 3
b^2 - 4ac = 7^2 - (4 x 2 x 3) = 49 - 24 = 25
2x^2 + 7x + 3 = 0
a = 2, b = 7, c = 3
b^2 - 4ac = 7^2 - (4 x 2 x 3) = 49 - 24 = 25
Answer:
Step-by-step explanation:
A quadratic equation can be factorised if and only if there are rational roots.
For any quadratic equation the discriminant decides about the nature of roots.
Thus only if the discriminant is a perfect square we can have rational roots and in this case only factorization is possible.
In the given equation
[tex]2x^2+ 7x+ 3 = 0\\a=2, b=7, c=3\\b^2-4ac = 1[/tex]
Since 1 is a perfect square we can factor and solve
[tex]2x^2 +7x +3 = 0\\(2x+1)(x+3)=0\\x=-1/2 or x = -3[/tex]