Answer:
-4
Step-by-step explanation
Given the standard form of a quadratic equation expressed as ax^2 + bx + c = 0
Comparing to the given equation 2x^2+6x+5=0
ax^2 = 2x^2
a = 2
bx = 6x
b = 6
c = 5
Get b^2 - 4ac
Substitute the values of a, b and c into b^2 - 4ac
b^2 - 4ac
= 6^2 - 4(2)(5)
= 36 - 40
= -4
Hence the value of b^2 - 4ac is -4