Respuesta :

dalendrk
If QRST is a rectangle then Q = 90°.

Threfore

5x + 30 = 90    |subtract 30 from both sides

5x = 60    |divide both sides by 5

x = 12
A rectangle is a four-sided flat shape where every angle is a right angle (90°). 

[tex]QRST = 90^0[/tex] 

[tex]5x + 30 = 90 [/tex]   

[tex]5x = 60[/tex]    

[tex]5x = 60 / 5[/tex]

[tex]x = 12[/tex]