Someone me with multiplying and dividing with scientific notation

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)

In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

Examine the two-step equation. − 7 4 + x 4 = 2 which property of operations allows you to add the same constant term to both sides? amultiplication property of equality bdivision property of equality caddition property of equality dsubtraction property of equality