Answer:
Each hot dog is worth 5.7
Each bun is worth 2.4
Explanation:
3d + 2b = 21.9
2d + 5b = 23.4
multiply the first by 2 and the second by 3
6d + 4b = 43.8
6d + 15b = 70.2
the coefficeint of d is the same in both equations, so subtract the first from the second
11b = 26.4
divide
b = 2.4
each bun is worth 2.4
take the first equation and plug the price of buns in
3d + 2b = 21.9
3d + 2(2.4) = 21.9
3d + 4.8 = 21.9
3d = 17.1
d = 5.7
each hot dog is worth 5.7
A method you could use to do this more easily or check your answers would be to graph the fuctions used on a website like desmos