SOLUTION: As i am not good at this can someone help me please and show me step by step so i can solve the other 19 questions i have thank you. Determine the number and type of roots for e

Algebra ->  Square-cubic-other-roots -> SOLUTION: As i am not good at this can someone help me please and show me step by step so i can solve the other 19 questions i have thank you. Determine the number and type of roots for e      Log On


   



Question 796789: As i am not good at this can someone help me please and show me step by step so i can solve the other 19 questions i have thank you.
Determine the number and type of roots for each equation
2X(X+2) =-2

Answer by josgarithmetic(39626) About Me  (Show Source):
You can put this solution on YOUR website!
First, divide left and right sides by 2.
X%28X%2B2%29=1.
X%5E2%2B2X=1
X%5E2%2B2X-1=0
Which you may TRY to factor. .....left side expressions seems unfactorable, and graph of the left side as a function might not cross the x-axis.

Discriminant? 2%2A2-4%2A1%28-1%29=4%2B4=8, and this is positive. I would expect two REAL roots, and that the function, X%5E2%2B2X-1 DOES IN FACT cross the x-axis. TWO REAL ROOTS.

Using solution to quadratic formula, they would be:
%28-2%2B8%29%2F2=3 and %28-2-8%29%2F2=-5++