Answer:
see explanation
Step-by-step explanation:
To solve the given quadratic equations, equate to zero, factorise and solve
given
x² - 19x + 48 = 0
Consider the factors of the constant term (+ 48) which sum to give the coefficient of the x- term (- 19)
The required factors are - 3 and - 16, hence
(x - 3)(x - 16) = 0
equate each factor to zero and solve for x
x - 3 = 0 ⇒ x = 3
x - 16 = 0 ⇒ x = 16
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given
x² + 21x - 100 = 0
Consider the factors of the constant term (- 100) which sum to give the coefficient of the x- term (+ 21)
The required factors are + 25 and - 4, hence
(x + 25)(x - 4) = 0
x + 25 = 0 ⇒ x = - 25
x - 4 = 0 ⇒ x = 4