Question

Solve 3x2 + 18x + 15 = 0 by completing the square.

3(x + 3)2 = 6; x = −3 + square root 2, x = −3 − square root 2

3(x + 9)2 = 12; x = −11, x = −7

3(x + 3)2 = 12; x = −5, x = −1

3(x + 9)2 = 228; x = −9 + square root 76, x = −9 − square root 76

Answer 1

@Hitaro9

Answer 2

@flowmaster1776 @W.W.G.D @quickstudent @texaschic101 @TheSmartOne @Preetha @Pi123 @darkprince14 @UsukiDoll @vera_ewing @naledimunetsi @Samus_Aran @Madgirlwithabluebox @Mrs.Irwin

Answer 3

YES PERSON

Answer 4

no mass tagging!

Answer 5

Whaaaaaat? I really need help and I didn't know it wasn't allowed... Sorry!

Answer 6

can you help though?

Answer 7

I got my own problems... if you know matlab that would be nice.

Answer 8

okay thanks anyway

Answer 9

Im not any good at math sorry :P

Answer 10

okay :(

Answer 11

darkprince?

Answer 12

I'm thinking D but I checked other places and That's not what anyone else got...

Answer 13

I just don't understand why

Answer 14

guys...?

Answer 15

Completing the square means we want to transform ax2 + bx + c into the form a(x+d)2 + e=0

Where d =b/2a
And e = c - (b^2 /4a)

Answer 16

so 3(x^2 + 6x + 8) + 228

Answer 17

that's what I got

Answer 18

UsukiDoll you're still here?

Answer 19

Note that 3x^2 + 18x + 15=0 is of the form ax^2 + bx + c=0
From there, find a, b and c and then apply them to the equation i have provided earlier