Question

I've never used the quadratic formula before I don't understand the formula... How would I solve for x?
2x^2-5x-4=0

Answer 1

Compare your quadratic equation with \(ax^2+bx+c=0\)
find \[a=...?\\b=...?\\c=...?\\\]
can you find those ?

Answer 2

2,5,4?

Answer 3

not actually, you have to account for - *minus* sign also.
so, a =2 is correct,
what about b,c ?

Answer 4

-5 and -4?

Answer 5

yes, those are correct,
now calculate \(b^2-4ac=....?\)

Answer 6

I'm not sure :/

Answer 7

you have a=2, b= -5, c=-4
just plug in values!
\(b^2-4ac=(-5)^2-4(2)(-4)=...?\)

Answer 8

25-8x-4

Answer 9

where does 'x' come from ??

Answer 10

or is it multiplication sign ?