Answer:
B
Step-by-step explanation:
Given a quadratic equation in standard form : ax² + bx + c = 0 : a ≠ 0
Then the nature of the roots may be determined using the discriminant.
Δ = b² - 4ac
• If b² - 4ac > 0 then 2 distinct real solutions
• If b² - 4ac = 0 then a real unique solution
• If b² - 4ac < 0 then no real solutions
5x² + 20x + 20 = 0 ← is in standard form
with a = 5, b = 20, c = 20, thus
b² - 4ac
= 20² - (4 × 5 × 20)
= 400 - 400
= 0
Hence the equation has one real unique solution → B
