Question

At a concession​ stand, seven hot dog(s) and four hamburger(s) cost ​$15.00​; four hot dog(s) and seven hamburger(s) cost ​$18.00. Find the cost of one hot dog and the cost of one hamburger.

Answer 1

hotdog $1, and hamburger $2

Explanation:

D-is hot dogs, H-hamburgers

7D +4H = 15

4D +7H = 18

we got 2 equations with 2 unknown so we can solve

7D +4H = 15 multiply by 7

4D +7H = 18 multiply by -4

49D +28H = 105

-16D -28H = -72 add the two equations

33D= 33 so D=$1

go back to the first equation:

7*1 +4H =15 gives us 4H = 15-7; 4H = 8 so H= $2