Answer:
[tex]1) 3x+45=90[/tex]
[tex]3x=90-45[/tex]
[tex]3x=45[/tex]
[tex]\frac{3x}{3} =\frac{45}{3}[/tex]
[tex]x=15[/tex]
1) The angles are complementary
[tex]--------[/tex]
[tex]2)x-20+x=90\\[/tex]
[tex]2x=90+20[/tex]
[tex]2x=110[/tex]
[tex]x=55[/tex]
2) The angles are complementary
[tex]--------[/tex]
[tex]3)2x+(3x+25)=180[/tex]
[tex]2x+3x+25=180[/tex]
[tex]2x+3x=180-25[/tex]
[tex]5x=155[/tex]
[tex]x=\frac{155}{5}[/tex]
[tex]x=31[/tex]
3) The angles are supplementary
[tex]----------[/tex]
hope it helps..
have a great day!!
