Answer:
[tex]x=20[/tex]
Step-by-step explanation:
we know that
[tex]x+100+3x=180[/tex]
so solve for x
[tex]4x+100=180\\\\4x=80\\\\x=\frac{80}{4}=20[/tex]
Answer: x = 20
180 - 100 = 80
4x = 80
x = 20