Answer:
Δ = 349
Step-by-step explanation:
Given a quadratic equation in standard form
ax² + bx + c = 0 ( a ≠ 0 ) , then the discriminant is
Δ = b² - 4ac
9x² + 5x - 9 = 0 ← is in standard form
with a = 9, b = 5 , c = - 9 , then
b² - 4ac
= 5² - (4 × 9 × - 9)
= 25 - (- 324)
= 25 + 324
= 349
