6. 21.9 X 0.7

what is this

Which shows one way to determine the factors of  x3  +  5x2  –  6x  –  30 by grouping? x(x2  –  5)  +  6(x2  –  5)x(x2  +  5)  –  6(x2  +  5)x2(x  –  5)  +  6(x  –  5)x2(x  +  5)  –  6(x  +  5)

Write two subtraction equations that are equivalent to 5 + 12 = 17.

What term makes it inconsistent y=2x - 4 ?