Pls answer anything you know here (Factoring) thanks

Can someone check if i did this correct. it’s number 4 if you’re wondering.

Use the linear combination method to solve the system of equations. explain each step of your solution. if steps are not explained, you will not receive credit for that step. 2 + 9 = −26 −3 − 7 = 13

What is the volume of a cardboard box that measures 1 inch by 5 inches by 7 inches? the volume of the cardboard is cubic inches. enter your answer as the number that correctly fills in the blank in the previous sentence. if necessary, round your answer to the nearest tenth, like this: 42.5