How do you solve this:Which of the following are solutions to the equation below?

x^2 + 3x - 18 = 0

Question

How do you solve this:Which of the following are solutions to the equation below?

x^2 + 3x - 18 = 0

anonymous · Answer

A. 	-6
  		B. 	18
  		C. 	6
  		D. 	-3
  		E. 	3
  		F. 	9

anonymous · Answer

check all that apply

hoblos · Answer

you can just try to plug in each answer and see if it makes the equation true

or you can factorize the equation and get the roots
do you know how to factorize it ?

jhonyy9 · Answer

can you factorized it ?

compassionate · Answer

x=-6,3

E

jpsmarinho · Answer

You can only use bhaskara, and encounter that 3 and -6 is roots of the equation

anonymous · Answer

teach me,ill write it down.

jpsmarinho · Answer

You first find the delta value that is :
 Delta= b^2 - 4*a*c

anonymous · Answer

x2 + 6x - 3x - 18
x(x+6) - 3(x+6)
(x-3)(x+6)

anonymous · Answer

3 & -6

hoblos · Answer

simply.. search for 2 numbers having a product of (-18) and sum of 3

they are 6 and -3

so the equation ends up to be

(x-3)(x+6) = 0
the roots are     x=3 and  x=-6

jpsmarinho · Answer

After, uses in this formula:
 X= (-b + square root of delta)/(2*a)

jpsmarinho · Answer

And  X= (-b - square root of delta)/(2*a)

jpsmarinho · Answer

The variables a, b and c is  : ax^2 + bx + c

anonymous · Answer

i see.so how would you do this one..the same way?

anonymous · Answer

x^2 - 11x + 24 = 0

jpsmarinho · Answer

8 and 3 . Yeah in the same way that is write above, using factorization or bhaskara

anonymous · Answer

ok then,thanks. i got it.