Question

For the function f(x) = x² + 4x - 45 solve the following. f(x)20 Select the correct choice below and fill in the answer box within your choice. O A. The solution is (Type your answer in interval notation.) OB. The solution is { }(Use a comma to separate answers as needed.)

Answer 1

f(x) = x² + 48-45 Now, f(x) 7,0 implies x² +42-45 70 => x² +92-52-9570 => x(x+9) - 5 (x+2) 7,0 = (x+)(x - 5) yo We know that if the product of two quantity is greaten or equal to zero then, either both of them are greater or equal to zero or both of them are less on equal to zero. O

Then we have, eithen, xtgyor and x-570 - A) ox, X+920 } - (Ⓡ) and x-5 co (A) We have, x7-9 and x 75 If x7, then obviously xy-gh ..we can take the solution as (275) have, from (B) we and x65 xs-9 if x-9 then obviously x 25 [57-g] . We can take the solution as xs-gl : We have a 2-9 and x5 as an solution can not set the 30, we interval Iso, the correct choice is option (B). The solution is { x = -9, x7,5}