Please help no one is answering my questions!

x - 4

The missing dimension of the prism is A

because the volume of the rectangular prism equals the product of the sides, we have:

V = (x - 1)(x - 3)A

but V = x³ - 8x² + 19x - 12

=> x³ - 8x² + 19x - 12 = (x - 1 )(x - 3)A

⇔ x²(x - 1) - 7x(x - 1) + 12(x - 1) = (x - 1)(x - 3)A

⇔ (x² - 7x + 12)(x - 1) = (x - 1)(x - 3)A

⇔ (x² - 3x - 4x + 12)(x - 1) = (x - 1)(x - 3)A

⇔ (x - 3)(x - 4)(x - 1) = (x - 1)(x - 3)A

⇒ A = x - 4

Step-by-step explanation: