[tex]\huge\text{Hey there!}[/tex]
[tex]\mathsf{5x + 3 + 9x - 20 = 151^\circ}[/tex]
[tex]\huge\textbf{COMBINE the LIKE TERMS}[/tex]
[tex]\mathsf{14x - 17 = 151^\circ}[/tex]
[tex]\huge\textbf{ADD 17 to BOTH SIDES}[/tex]
[tex]\mathsf{14x - 17 + 17 = 151 + 17}[/tex]
[tex]\huge\textbf{SIMPLIFY IT!}[/tex]
[tex]\mathsf{14x = 151 + 17}[/tex]
[tex]\mathsf{14x = 168}[/tex]
[tex]\huge\textbf{DIVIDE 14 to BOTH SIDES}[/tex]
[tex]\mathsf{\dfrac{14x}{14} = \dfrac{168}{14}}[/tex]
[tex]\huge\textbf{SIMPLIFY IT!}[/tex]
[tex]\mathsf{x = \dfrac{168}{14}}[/tex]
[tex]\mathsf{x = 12}[/tex]
[tex]\huge\textbf{Thus, your answer should be: \boxed{\mathsf{x = 12}}}\huge\checkmark[/tex]
[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]
~[tex]\frak{Amphitrite1040:)}[/tex]