Answer:
[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{r = - 6}}}}}[/tex]
Step-by-step explanation:
[tex] \sf{5(r + 9) - 2(1 - r) = 1}[/tex]
Distribute 5 through the parentheses
Similarly, distribute 2 through the parentheses
[tex] \longrightarrow{ \sf{5r + 45 - 2 + 2r = 1}}[/tex]
Collect like terms
[tex] \longrightarrow{ \sf{7r + 45 - 2 = 1}}[/tex]
Subtract 2 from 45
[tex] \longrightarrow{ \sf{7r + 43 = 1}}[/tex]
Move 43 to right hand side and change it's sign
[tex] \longrightarrow{ \sf{7r = 1 - 43}}[/tex]
Subtract 43 from 1
[tex] \longrightarrow{ \sf{7r = - 42}}[/tex]
Divide both sides by 7
[tex] \longrightarrow{ \sf{ \frac{7r}{7} = \frac{ - 42}{7}}} [/tex]
Calculate
[tex] \dashrightarrow{ \sf{r = - 6}}[/tex]
Hope I helped!
Best regards! :D
