X:2,4,6,8 y:8,4,0,-4 does this table represent a non or linear function

The square root of 9x plus 7 plus the square rot of 2x equall to 7

Acomputer store buys a computer system at a cost of $370.80. the selling price was first at $ 618, but then the store advertised a 20 % markdown on the system. answer parts a and b. a. find the current sale price.

Solve for p: 21 , = 3/4 pit's fraction problem