Answer: See explanation
Explanation:
The information given in the question can be turned into an equation as:
2u + y = 30 ........ i
5u + y = 42 ........ ii
Subtract i from ii
3u = 12
u = 12/3 = 4
A pair of socks cost $4
Since 2u + y = 30
2(4) + y = 30
8 + y = 30
y = 30 - 8 = 22
A pair of slippers cost $22