Array around Slope and Intercept Formula

Hello all......I'm hoping someone can help me with an array formula please. I'm trying to put in this formula:

=SLOPE($C$2:$C$7602,$B$2:$B$7602)*B2-ABS(INTERCEPT($C$2:$C$7602,$B$2:$B$7602))

but with an array around it. I've attached an example of my file and what I'm after is an IF statement around it to say that I want the =SLOPE etc formula to calculate IF($A$2:$A$28=A2).

Thanks in advance.