Answer:
B
Explanation:
x² - 9x + 20 = 0 ← in standard form
consider the factors of the constant term (+ 20) which sum to give the coefficient of the x- term (- 9)
the factors are - 4 and - 5 , since
- 4 × - 5 = + 20 and - 4 - 5 = - 9 , then
(x - 4)(x - 5) = 0 ← in factored form
equate each factor to zero and solve for x
x - 4 = 0 ( add 4 to both sides )
x = 4
x - 5 = 0 ( add 5 to both sides )
x = 5
solutions are x = 4 , x = 5