Tolong di bantu no 10,11,12 isi cara ya di kumpul besok

10) 3x - 2 + 2x + 2 = 180
5x = 180
x = 36
maka sudut abd = 3x -2 = 3×36-2 = 106

11)
[tex] \alpha + \beta = 90 \\ \frac{1}{2} \beta + \beta = 90 \\ \frac{3}{2} \beta = 90 \\ \beta = 60[/tex]
[tex]lalu \: cari \: \alpha \\ \alpha = \frac{1}{2} \beta \\ \alpha = \frac{1}{2} 60 \\ \alpha = 30[/tex]