Final answer:
Two expressions that are equivalent to 8(-10x + 3.5y - 7) are -80x + 28y - 56 and 640x - 224y + 448. The correct options are a. and c.
Step-by-step explanation:
To find the expressions that are equivalent to 8(-10x + 3.5y - 7), we distribute the 8 to each term inside the parentheses:
8(-10x) + 8(3.5y) + 8(-7)
This simplifies to -80x + 28y - 56. Therefore, option a. (-80x + 28y - 56) is an equivalent expression to 8(-10x + 3.5y - 7). Additionally, option c. (640x - 224y + 448) is also equivalent to 8(-10x + 3.5y - 7). Therefore, the correct options are a. and c.