If the product (3x^2 - 5x + 4)(7 - x) can be written in the form ax^3 + bx^2 + cx + d, where a,b,c,d are real numbers, then find 8a + 4b + 2c + d.
\((3x^2-5x+4)(7-x) = -3x^3+26x^2-39x+28\)
a = -3, b = 26, c = -39 and d = 28
8a + 4b + 2c + d = 30
Alternatively \[ 8a+4b+2c+d =a\cdot 2^2 + b\cdot 2^2 + c\cdot 2+d = (3\cdot 2^2-5\cdot 2 +4)(7-2) = 6\cdot 5 = 30. \]