Answer :

To determine which answer choice (if any) contains all the roots of the equation [tex]\( -12x^2 = 60x + 75 \)[/tex], let's proceed with the necessary algebraic steps:

1. Rewrite the equation in standard form:

The given equation is:
[tex]\[ -12x^2 = 60x + 75 \][/tex]

To get this into the standard quadratic form [tex]\(ax^2 + bx + c = 0\)[/tex], we move all terms to the left side of the equation:
[tex]\[ -12x^2 - 60x - 75 = 0 \][/tex]

2. Solve the quadratic equation:

We can solve this quadratic equation using the quadratic formula:
[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]
Here, [tex]\( a = -12 \)[/tex], [tex]\( b = -60 \)[/tex], and [tex]\( c = -75 \)[/tex].

Calculate the discriminant ([tex]\(\Delta\)[/tex]):
[tex]\[ \Delta = b^2 - 4ac = (-60)^2 - 4(-12)(-75) \][/tex]
[tex]\[ \Delta = 3600 - 3600 = 0 \][/tex]

3. Determine the roots:

Since the discriminant is zero ([tex]\(\Delta = 0\)[/tex]), the quadratic equation has exactly one real double root (real and repeated root):
[tex]\[ x = \frac{-b}{2a} = \frac{-(-60)}{2(-12)} = \frac{60}{-24} = -2.5 \][/tex]

So, the root of the equation is:
[tex]\[ x = -2.5 \][/tex]

4. Match the roots to the answer choices:

The given answer choices are:
[tex]\[ \text{1. } x = 0, 3 \][/tex]
[tex]\[ \text{2. } x = \pm 2.5 \][/tex]
[tex]\[ \text{3. } x = 3, -2.5 \][/tex]
[tex]\[ \text{4. } x = -2.5 \][/tex]

We found that the only root is [tex]\( x = -2.5 \)[/tex]. Among the choices, only choice 4 ( [tex]\( x = -2.5 \)[/tex] ) matches the solution.

Hence, the correct answer is:
[tex]\[ \boxed{4} \][/tex]

Note that none of the other answer choices include `-2.5` exclusively or correctly include additional extraneous roots.