Given that lines \( M \) and \( N \) are parallel and angle 1 measures \( 135^\circ \), we can determine the measure of angle 7 using the properties of parallel lines and transversals.
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Angle 1 and angle 5 are corresponding angles because they are both formed by the transversal intersecting the two parallel lines. Since corresponding angles are equal when two lines are parallel, we have: \[ \text{Angle 5} = \text{Angle 1} = 135^\circ \]
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Angles 5 and 7 are also supplementary because they are on a straight line formed by the transversal at line \( N \). Therefore: \[ \text{Angle 5} + \text{Angle 7} = 180^\circ \]
Substituting the measure of angle 5: \[ 135^\circ + \text{Angle 7} = 180^\circ \]
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Solving for angle 7: \[ \text{Angle 7} = 180^\circ - 135^\circ = 45^\circ \]
Thus, the measure of angle 7 is \( \boxed{45^\circ} \).