Answer:
[tex]\boxed{\sf x =40}[/tex]
Step-by-step explanation:
[tex]\sf 12x=34^2 - 26^2[/tex]
Solve the square.
[tex]\sf 12x=1156-676[/tex]
[tex]\sf 12x=480[/tex]
Divide both sides by 12.
[tex]\displaystyle \sf \frac{12x}{12} =\frac{480}{12}[/tex]
[tex]\sf x =40[/tex]
