Best Answer

Several options:

- Draw it and measure the missing side.
- Use coordinate geometry. You can draw the base and two of the sides since you know the angles that these lines make and their lengths. You therefore know their upper end points and so calculating the length of the fourth side is trivial.
- Consider the triangle ABC. Sides AB and BC are known as is angle ABC. So you can use the sine rule to calculate AC and angles CAB and ACB. Angle DAB is known so angle DAC = DAB - CAB, angle ACD = BCD - ACB. In triangle ACD, two angles are known so all three are known. Use the sine rule again to find CD.

Q: How do you find the unknown side of a quadrilateral with 3 known sides and 4 angles?

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No. Triangles have three angles and three sides. A quadrilateral has four angles and four sides.

A quadrilateral has four angles. There are always the same number of angles as there are sides, so since a quadrilateral has four sides it must also have four angles.A quadrilateral doesn't "do" any angles. However, it has four angles. (If that is what you wanted to know.)

A quadrilateral is a polygon with four sides and angles.

A square is a quadrilateral with four equal sides and four right angles.

A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.

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No. Triangles have three angles and three sides. A quadrilateral has four angles and four sides.

A quadrilateral has four angles. There are always the same number of angles as there are sides, so since a quadrilateral has four sides it must also have four angles.A quadrilateral doesn't "do" any angles. However, it has four angles. (If that is what you wanted to know.)

It's impossible for a quadrilateral to have no equal sides and have right angles.

A quadrilateral has 2 pair of congruent angles and 4 congruent sides. What is the name of the quadrilateral

An impossibility. By definition a quadrilateral with 4 congruent sides must have congruent adjacent angles.

A quadrilateral is a polygon with four sides and angles.

There are four angles in a trapezoid since a trapezoid is a quadrilateral. A quadrilateral has four sides and four angles.

A square is a quadrilateral with four equal sides and four right angles.

A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.A quadrilateral is any polygon with 4 sides - and hence with 4 angles. Those angles may, or may not, be congruent.

A quadrilateral shape has four sides and four internal angles. A triangle has three sides and three internal angles. Therefore there is no such thing as a quadrilateral triangle.

4 sides and 4 interior angles

A quadrilateral with 4 equal sides and 4 right angles is a square.