Answer:
2x² - 12 + 8x
Setting up the equation:
Let that [SOMETHING] be L
- ⇒ 3x² + 8x - 16 - (L) = x² - 4
To avoid confusion, let's use parenthesis:
- ⇒ (3x² + 8x - 16) - (L) = (x² - 4)
Simplifying the equation:
Subtract "(3x² + 8x - 16)" both sides to isolate "(L)":
- ⇒ (3x² + 8x - 16) - (3x² + 8x - 16) - (L) = (x² - 4) - (3x² + 8x - 16)
- ⇒ -(L) = (x² - 4) - (3x² + 8x - 16)
Take the "-" in the parenthesis:
- ⇒ -(L) = (x² - 4) + (-3x² - 8x + 16)
Open the parenthesis:
- ⇒ -L = x² - 4 - 3x² - 8x + 16
Combine like terms and simplify:
- ⇒ -L = x²(1 - 3) + (-4 + 16) - 8x
- ⇒ -L = x²(-2) + (12) - 8x
- ⇒ -L = -2x² + 12 - 8x
Put both terms in parenthesis:
- ⇒ -(L) = (-2x² + 12 - 8x)
Multiply both sides by -1:
- ⇒ (L) = -(-2x² + 12 - 8x)
- ⇒ L = 2x² - 12 + 8x
Thus, the [SOMETHING] is 2x² - 12 + 8x.
