Question

Please help, this is for my best friend.

Answer 1

`y = - (3)/(20) x + 900 \\ \\ y = - (20)/(3) x + 6000`

Explanation:

`\\ part \: a. \:( food \: expenses) \\ to \: solve \: these \: problems \: we \: surmone \\ \: the \: following \: laws : \to \\m = ( y_(2) -y_(1) )/(x_(2) - x_(1)) = (815 - 812)/(390 - 410) = - (3)/(20) = - 0.15 \\ the \: general \: slope \:i ntercept \: form \: is : \\ y = mx + c \\ to \: find \: c \: lets\: insert \: any \: two \: pairs \: for \: x \: and \: y \to \\ 812 = - (3)/(20) (410) + c \\ 16,240 = - 3(410) + 20c \\ c = (1747)/(2) \\ c = 873.5 \\ \\ therefore \: y = - (3)/(20) x + 900 \: (i.e \: to \: he \: nearest \: thousand). \\ \\ \\ part \: b. \: (medical \: expenses) \\ to \: be \: able \: to \: solve \: these \: problems \: we \: surmone \\ \: the \: following \: laws : \to \\m = ( y_(2) -y_(1) )/(x_(2) - x_(1)) = (390 - 410)/(815 - 812) = - (20)/(3) = - 6.667 \\ the \: general \: slope \:i ntercept \: form \: is : \\ y = mx + c \\ lets \: find \: c \: by \: insert \: any \: two \: pairs \: for \: x \: and \: y \to \\ 410 = - (20)/(3) (812) + c \\ 1230 = - 20(812) + 3c \\ c = (17470)/(3) \\ c = 5823.3333 \\ \\ therefore \: y = - (20)/(3) x + 6000 \: (i.e \: to \: he \: nearest \: thousand). \\ \\`