Respuesta :

Answer:

[tex]42 = - 48 + 3r[/tex]

add 48 to either sides:

[tex]42 + 48 = ( - 48 + 3r) + 48 \\ 90 = 3r \\3r = 90[/tex]

divide all sides by 3:

[tex] \frac{3r}{3} = \frac{90}{3} \\ \\ { \boxed{ \boxed{r = 30}}}[/tex]

fnej

Answer:

r = 30

Step-by-step explanation:

42 = -48 + 3r

  • First, we will add 48 to both sides so that r can be isolated

42 + 48 = -48 + 48 + 3r

  • Then, we will add

90 = 3r

  • Then to isolate r, we have to get rid of the 3
  • To get rid of the 3, we will divide by 3 on both sides

[tex]\frac{90}{3} =\frac{3r}{3}[/tex]

  • Then, divide

30 = r