What is the value of #y# in #y+4x =9#, when #x = -2, 0, 3#?

1 Answer
Sep 15, 2017

when #x# = -2, #y# = 17
when #x# = 0, #y# = 9
when #x# = 3, #y# = -4

Explanation:

Rearrange the equation by isolating #y# then plugin either #-2#, #0# or #3# for where #x#, since #x# equals those values

Rearrange first,
#y# = -#4x# + 9

  • When #x# = -2,
    #y# = -4(-2) + 9
    #y# = 8 + 9
    #y# = 17

  • When #x# = 0
    #y# = -4(0) + 9
    #y# = 9

  • When #x# = 3
    #y# = -4(3) + 9
    #y# = -12 + 9
    #y# = -4

Therefore
when #x# = -2, #y# = 17
when #x# = 0, #y# = 9
when #x# = 3, #y# = -4