Question

What is the value of b^2 - 4ac for the following equation? x^2 + 5x + 4 = 0

A.) 9
B.) 16
C.) 25

Answer 1

5^2 - 4*1*4= 25-16=9

Answer 2

Well the 'a' 'b' and 'c' represent the coefficients of the polynomial...

So a = 1
b = 5
c = 4

So

\[\large b^2 - 4ac\]

becomes
\[\large 5^2 - 4(1)(4)\]
\[\large 25 - 16 = ?\]

Answer 3

9..!

Answer 4

Indeed!

Answer 5

What about this one?
2x^2 - 2x - 1 = 0

Answer 6

-2^2 - 4*2*-1 = 4- (-8) or 4+8=12

Answer 7

And this one? 5x^2 + 7x = 6

Answer 8

do the same thing. a=5, b=7, c=-6 because you'd move the 6 over to make the equation =0. so you'd have 5x^2+7x-6=0