which formula would i use to solve this equation?

First divide through by the common factor of 4:

x^2 + 7x + 12 = 0

You can factorise this easily (two numbers that add up to 7 and multiply to 12: 3 and 4)

∴ (x + 3) (x + 4) = 0

∴ x = -3 or x = -4.

The quadratic one

or factorise

4x^2 + 28x + 48 = 4(x^2 + 7x + 12) = 4(x+3)(x+4) = 0

==> x = -3 or x = -4

I would factor the polynomial. First factor out a 4, giving

x^2+7x+12 = 0 which factors to (x+4)(x+3) = 0

So the question is, what values of x make that equation true? The answers are

x=-4 and x=-3

If you can factor, the binomial formula is overkill.

Well I guess you're a Tigers supporter. I'll help you because MANLY are in the grand final and I'm feeling generous.

No formula needed:

Divide by 4:

x^2 + 7x + 12 = 0

Factorise:

(x+4)(x+3) = 0

x+4=0 or x+3 = 0

x = -4 or -3

GO SEA EAGLES

if

ax^2 + bx + c = 0

then

x = [ -b ± (b^2 - 4ac)^1/2 ] / 2a

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