120^\circ
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
If $\angle ABC$ is a straight angle, give the number of degrees in the measure of $\angle ABD$. [asy] pair A,B,C,D; A = dir(180); D = dir(60); C = dir(0);
draw(B--1.2*A,EndArrow); draw(B--1.2*D,EndArrow); label("A",A,S); dot(A);
label("B",B,S); draw(B--1.2*C,EndArrow); label("C",C,S); label("D",D,dir(135));
label("$6x^{\circ}$",B,NW); label("$3x^{\circ}$",B+.1,NE); dot(D); dot(C);
[/asy]
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
120^\circ
If $\angle ABC$ is a straight angle, give the number of degrees in the measure of $\angle ABD$. [asy] pair A,B,C,D; A = dir(180); D = dir(60); C = dir(0);
draw(B--1.2*A,EndArrow); draw(B--1.2*D,EndArrow); label("A",A,S); dot(A);
label("B",B,S); draw(B--1.2*C,EndArrow); label("C",C,S); label("D",D,dir(135));
label("$6x^{\circ}$",B,NW); label("$3x^{\circ}$",B+.1,NE); dot(D); dot(C);
[/asy]
train