Step 1. Supplementary angles add up to 180 degrees.
Step 2. Let x the angle and 4x be its supplementary angle.
Step 3. Then x+4x=180 or 5x=180. Divide by 5 to both sides to get x=36 degrees. With x=36 then 4x=144 degrees.
Step 4. ANSWER: The larger supplementary angle is 144 degrees.
I hope the above steps were helpful.
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