Which shows one way to determine the factors of x3 – 12x2 – 2x + 24 by grouping?

x(x2 – 12) + 2(x2 – 12)
x(x2 – 12) – 2(x2 – 12)
x2(x – 12) + 2(x – 12)
x2(x – 12) – 2(x – 12)

The last  choice.

Step-by-step explanation:

x3 – 12x2 – 2x + 24            Take out  x2  and -2:

= x2(x – 12) - 2(x – 12).

The x - 12 is common to the 2 parts so the factors are:

(x2 + 2)(x - 12).

the sum of all the angles in a triangle are equal to 180

so you can add   the 3 given angles together to equal 180:

5y + 2y + 2y = 180

or since all three angles have the same letter, combine the 3 angles to equal 180:

9y = 180