Answer:
x=4
Step-by-step explanation:
8x - 7 =2(2x +7) - 5
8x - 7 =4x +14 - 5
8x - 7 =4x +9
8x - 4x =9 +7
4x =16
x=16 :4
x=4
Answer with Step-by-step explanation:
We are given that

when x<9
when 
LHD

=
RHD



Hence, the function is not differentiable at x=9
I think it is x > 5 because if you combine like terms you would get 2x-4>6 then you add 4 To 6 which is 10 then you do 10÷2 which is 5