Help pls :c
Need help with this calculus graph question

Adam plans to choose a video game from the section of the store where everything is 75% off. he writes the expression d-0.75d to find the sale price of the game if the original price is d dollars. gena correctly writes another expression, 0.25d, that will also find the sale price of the game if the original price is d dollars. use the drop down menus to explain each part of adams and rena's expression

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

What are two numbers that add up to -9 and multiply to -10 best answer gets branliest and 100 extra points