Answer:
There are 3 adults in the family.
Step-by-step explanation:
The equations 8x + 4y = 32 and 16x + 12y = 72 represent the cost of lunch and dinner for a family in which x is the number of adults and y is the number of children.
We have to find the number of adults or the value of x by solving these equations.
equations are 8x + 4y = 32 -------(1)
16x + 12y = 72 --------(2)
Now we will multiply equation 1 by 3 and subtract it by equation 2.
(16x + 12y) -3(8x + 4y) = 72 - 96
16x + 12y - 24x - 12y = -24
(16x - 24x) + (12y - 12y) = -24
-8x = - 24
8x = 24
x = 3
Therefore, there are 3 adults in the family.
