Let c represent candy and s soda.
2c+s=8
c+s=5.5
Solving the pair of simultaneous equations by eliminating s,
c=2.5
Representing the value of c in equation 1;
5+s=8
s=3
So, a box of Candy costs 2.5 and a soda costs 3
The answer is D. 1.601 * 10^9
We can check by subbing in the values.
7x + 2y = -7
(7,9).....x = 7 and y = 9
now we sub
7(7) + 2(9) = -7
49 + 18 = -7
67 = -7 (incorrect)....therefore, (7,9) is NOT a solution for this equation