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If, in the quadrilateral JKLM, the measures of the angles J, K, L, and M are in the ratio 2:3:5:6, then the quadrilateral is a:
Kite
parallelogram
trapezium
square
trapezium
Let angles be 2x, 3x, 5x, and 6x. Their sum is 2x+3x+5x+6x=16x=360┬░, giving x=22.5┬░. The angles are 45┬░,67.5┬░,112.5┬░,135┬░. Since no pair of adjacent or opposite sides/angles satisfies parallel or kite properties (such as equal adjacent sides or parallel opposite sides), check standard quadrilateral classifications. Specifically, opposite angles do not sum to 180┬░ and are not equal. Wait, let us check trapezium: a trapezium requires at least one pair of parallel sides, which corresponds to consecutive angles summing to 180┬░ (45┬░+135┬░=180┬░ and 67.5┬░+112.5┬░=180┬░). Therefore, adjacent angles on two sides sum to 180┬░, meaning two sides are parallel!
Ratio of angles J, K, L, and M of quadrilateral JKLM is 2 : 3 : 5 : 6
Sum┬аof┬аinterior┬аangles┬аof┬аa┬аquadrilateral=360┬░
Let angles be 2x, 3x, 5x, and 6x. Their sum is 2x+3x+5x+6x=16x=360┬░, giving x=22.5┬░. The angles are 45┬░,67.5┬░,112.5┬░,135┬░. Since no pair of adjacent or opposite sides/angles satisfies parallel or kite properties (such as equal adjacent sides or parallel opposite sides), check standard quadrilateral classifications. Specifically, opposite angles do not sum to 180┬░ and are not equal. Wait, let us check trapezium: a trapezium requires at least one pair of parallel sides, which corresponds to consecutive angles summing to 180┬░ (45┬░+135┬░=180┬░ and 67.5┬░+112.5┬░=180┬░). Therefore, adjacent angles on two sides sum to 180┬░, meaning two sides are parallel!
Students often assume that any quadrilateral with non-equal angles must be a general quadrilateral without realizing that adjacent angles summing to 180┬░ implies parallel sides (trapezium).
Step 1: Set up the angle ratio
Let the measures of angles J, K, L, and M be 2x, 3x, 5x, and 6x respectively.
J:K:L:M=2x:3x:5x:6x
Step 2: Apply sum of angles in a quadrilateral
The sum of all interior angles of a quadrilateral is always 360┬░. Therefore, set up the sum equation and solve for x.
2x+3x+5x+6x=360┬░тЯ╣16x=360┬░тЯ╣x=22.5┬░
Step 3: Calculate individual angles
Substitute x=22.5┬░ into each angle expression: Angle J=2(22.5┬░)=45┬░, Angle K=3(22.5┬░)=67.5┬░, Angle L=5(22.5┬░)=112.5┬░, Angle M=6(22.5┬░)=135┬░.
тИаJ=45┬░,тИаK=67.5┬░,тИаL=112.5┬░,тИаM=135┬░
Step 4: Identify the quadrilateral type
Notice that тИаJ+тИаM=45┬░+135┬░=180┬░ and тИаK+тИаL=67.5┬░+112.5┬░=180┬░. Since consecutive interior angles on two sides are supplementary, the opposite sides are parallel, which defines a trapezium.
Trapezium
C is correct because the sum of consecutive interior angles equals 180┬░, which confirms that the quadrilateral is a trapezium.
In any polygon problems involving angle ratios, always check if consecutive interior angles sum to 180┬░ to immediately identify parallel lines and trapeziums.