Okay. I will list all the relatively prime numbers up to 331. 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101, 103,107,109,113,127,131,137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331. Okay, so look at this list and see which match up. For A. 102 and 312. Neither of these numbers are relatively prime. For B. 10 and 45. Neither of these are relatively prime. For C. 3 and 51. 3 is a relatively prime number, 51 is not. For D. 35 and 72. Neither of these are relatively prime numbers. But the answer would be D. because to get a relatively prime pair of numbers you have to have both of them not be divisible by the same number. 102 and 312 can be divided 2, so that's not the answer. 10 and 45 can be divided by 5, so that is incorrect. 3 and 51 can be divided by 3, so that is also incorrect. 35 and 72 cannot be divided by the same numbers. So, the answer is D. 35 and 72.
So to find the slope of each airplane, you use the formula y2-y1/x2-x1. That means, for airplane#1 the equation will be 9-4/15-2. Simplify this and get 5/13. Then, for airplane#2, the equation will be 12-9/6-15. Simplify this and get 3/-9 and divide each side by 3 to get 1/-3 or -1/3. Next, use point slope formula to find the system of linear equations. Point slope formula is y-y1=m(x-x1). M is the slope. Use any point from the line. In this case, I will use (2,4). Tat means the first airplane's equation would be y-4=5/13(x-2). Then y-4=5/13x-10/13. Then, convert four into a fraction with a denominator of 13. This means, you have to multiply 4 by 13 to get 52/13. Add 52/13 to -10/13 to get 42/13. That means the first equation will be y=5/13x+42/13. The second equation point will be (6,12). This means the equation will be y-12=-1/3(x-6). Simplify this to get y-12=-1/3x+2. Simplify this to get y=1/3x+14. Therefore, Airplane#1 equation will be y=5/13x+42/13 and airplane #2 equation will be y=1/3x+14.
