Hi Mary. Okay, so I will try to make this as compact as I can. Vectors (in 2 dimensions) have an x component and a y component, and thus are written as either (x,y) or xi+yj, though both mean the same thing. For your questions, two useful formulas would be x=rcosθ and y=rsinθ, where r is the length, or magnitude, of the vector and θ is the angle usually between the vector and the x axis. So, for your first problem, you could rewrite vector r as r=(15cos70°,15sin70°), or if you prefer, r=15cos70°i + 15sin70°j. Do the same for vector s. Then just add the x components together (and that will be your final a) and add your y components together (and that will be your final b). It's totally fine to get decimals as answers here, by the way (and also, don't forget to make sure your calculator is in degree mode, just as a reminder). Thus you will have your answer ai+bj. You would do part b. the same way. I hope this helps Mary. Have a wonderful day!
