The intersection of lines \(l\) and \(m\) forms the 4 angles \(\angle{A}\), \(\angle{B}\), \(\angle{C}\), and \(\angle{D}\). The measure of \(\angle{B}\) is \(3\dfrac{1}{2}\) times the measure of \(\angle{A}\). Which of the following values is closest to the measure of \(\angle{A}\) ?

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The intersection of two lines will create two pairs of congruent angles. The four angles should add up to \(360^\circ\).

$$ 2x+2y = 360 $$

If one angle is \(3\dfrac{1}{2}\) times the other:

$$ x = 3\frac{1}{2}(y) $$ $$ x= \frac{7}{2}y $$

After substituting:

$$ 2\left(\frac{7}{2}\right)y+2y = 360 $$ $$ 7y+2y = 360 $$ $$ 9y = 360 $$ $$ y= \boxed{40} $$