Can somebody plz help me

A

Step-by-step explanation:

2x²-2x-9=0

this is a quadratic equation so we will use the quadratic formula .

 Δ= b²-4*a*c

let's calculate Δ to khow how many solutions this equations have .

 Δ= (-2)²-4*2*(-9)

    = 76

 we notice that 76>0

so this equation has two solutions :  (-b-√76)/4 and (-b+√76)/4

the trick here is to notice that :

=

      =

      = 2

Now we will simplify Δ by factoring by 2

so the answer is a .

add an image

step-by-step explanation:

answer: 48

just remember to use pemdas:

parentheses

expressions

multiplication

division

addition

subtraction