Let $a = 1 + i$ and $b = 4 + 7i.$  The complex number $c$ lies on the line segment connecting $a$ and $b$ so that the distance between $a$ and $c$ is equal to twice the distance between $c$ and $b.$  Find $c.$
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Let $a = 1 + i$ and $b = 4 + 7i.$  The complex number $c$ lies on the line segment connecting $a$ and $b$ so that the distance between $a$ and $c$ is equal to twice the distance between $c$ and $b.$  Find $c.$
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
3 + 5i
Let $a = 1 + i$ and $b = 4 + 7i.$  The complex number $c$ lies on the line segment connecting $a$ and $b$ so that the distance between $a$ and $c$ is equal to twice the distance between $c$ and $b.$  Find $c.$
train