Question

Substitution again help please

Answer 1

Explanation:

1) 4x -3

x = -7 ;

4x - 3 = 4*(-7) - 3 = - 28 - 3 = -31

x = 14 ;

4x - 3 = 4*14 - 3 = 56 - 3 = 53

x = 0

4x - 3 = 0 - 3 = -3

2) 6 -3x

x = -7 ;

6 - 3x = 6 - 3*(-7) = 6 + 21 = 27

x = 14

6 - 3x = 6 - 3*14 = 6 - 42 = -36

x = 0

6 - 3x = 6 - 0 = 6

`3) (3x - 21)/(7)\\\\x = -7\\\\\\(3*(-7)-21)/(7)=(-21-21)/(7)=(-42)/(7)=-6\\\\\\x = 14\\\\(3*14-21)/(7)=(42-21)/(7)=(21)/(7)=3\\\\\\x=0\\\\(0-21)/(7)=(-21)/(7)=-3\\\\`

4)

`(3x)/(7)-21\\\\\\x = -7\\\\(3*(-7))/(7)-21=-3-21=-24\\\\\\x =14\\\\(3*14)/(7)-21=3*2-21=6-21=-15\\\\\\x=0\\\\(0)/(7)-21=-21`