Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

The base and the perpendicular height are at right angles to each other. The measurements used must be in the same units. For example, to work in cm a 45 mm measurement would have to be converted to ...

There are two ways to construct a triangle using a ruler and a protractor. The first is a Side, Angle, Side (SAS) construction where two sides and the angle between them is known. The second is an ...

Understanding different types of angles and that angles in a triangle sum to 180° can be helpful when classifying a triangle. Recognising line symmetry and rotational symmetry will also help. Look for ...

Prove two triangles are congruent by showing they satisfy one of four criteria. Find missing lengths by using the scale factor. The relationship between similar shapes may be expressed as a ratio.

The sides of right-angled triangles are labelled opposite, hypotenuse and adjacent. Trigonometry explores the relationship between sides and angles in right-angled triangles. The hypotenuse is the ...

WHAT YOU NEED: two pieces of paper/card, pencil, scissors, ruler. Image caption, STEP 1: Place one piece of card on top of the other and use the ruler to draw a line from the bottom left corner of the ...

Trigonometry close trigonometryThe study of sides and angles in triangles. can be used to find a missing angle in a right-angled triangle when two sides are known. An understanding of the three ...

The three angles in a triangle add up to \(180^\circ\). If two of the angles are known then the third can be calculated by following these steps: Add the two known angles together. Subtract the total ...

Use a ruler, protractor and a pair of compasses to construct a triangle accurately. After the triangle has been constructed, leave the construction lines visible so each stage of the process is shown ...