Answer:
b² - 4ac = 349
Step-by-step explanation:
given a quadratic equation in standard form
• ax² + bx + c = 0 ( a ≠ 0 )
Then the discriminant is
• b² - 4ac
given
x² + 5x - 81 = 0 ← in standard form
with a = 1 , b = 5 , c = - 81 , then
b² - 4ac = 5² - ( 4 × 1 × - 81 ) = 25 - (- 324) = 25 + 324 = 349
