Respuesta :
Answer:
x = - 7, x = 5
Step-by-step explanation:
To find the zeros equate f(x) to zero, that is
x² + 2x - 35 = 0
To factorise the quadratic
Consider the factors of the constant term (- 35) which sum to give the coefficient of the x- term (+ 2)
The factors are + 7 and - 5, since
7 × - 5 = 35 and 7 - 5 = + 2, hence
(x + 7)(x - 5) = 0
Equate each factor to zero and solve for x
x + 7 = 0 ⇒ x = - 7
x - 5 = 0 ⇒ x = 5
ANSWER
[tex]x = - 7 \: or \: x = 5[/tex]
EXPLANATION
The given function is
[tex]f(x) = {x}^{2} + 2x - 35[/tex]
To find the zeros, we equate the function to zero.
[tex] {x}^{2} + 2x - 35 = 0[/tex]
Split the middle term to obtain,
[tex]{x}^{2} + 7x - 5x- 35 = 0[/tex]
Factor by grouping:
[tex]{x}(x + 7) - 5(x + 7)= 0[/tex]
[tex](x + 7)(x - 5) = 0[/tex]
[tex](x + 7) = 0 \: or \: (x - 5) = 0[/tex]
.
[tex]x = - 7 \: or \: x = 5[/tex]