Answer:
1. The figure did not indicate that it is a right angle but let's assume that it is.
[tex]5x+30=90[/tex]
[tex]5x=90-30[/tex]
[tex]x=12[/tex]
2. The two angles are supplementary; hence, their sum is 180°
[tex]10x+5+8x-5=180[/tex]
[tex]18x=180[/tex]
[tex]x=10[/tex]
3. Vertical angles are equal; therefore,
[tex]7x-3=6x+1[/tex]
[tex]7x-6x=1+3[/tex]
[tex]x=4[/tex]
