13. A kitchen fl oor is covered in tiles; there is no space between the tiles. Each rectangular tile is 20 cm in width and 30 cm in length. Using the diagram belowto count the tiles, fi nd the area of fl oor covered by the tiles.
30 cm 20 cm
14. A rectangle has a perimeter of 320 m and its length is three times its width. Find the measure of:
(i) the length and width of the rectangle
(ii) the area of the rectangle.
15·2 Introduction to triangles
A triangle is a polygon that has three sides and three angles.
Construct a triangle, given the lengths of the three sides 10 1
Draw a rough sketch of the triangle to be constructed. Include all given information in your sketch.
A 3
With compass point on A and compass width equal to one of the other lengths given, draw an arc as shown.
C 2
By the end of this section you should be able to: ● identify the parts of a triangle ● construct a triangle given the lengths of the three sides
Draw a line segment [AB] which has a length equal to the longest length given.
B 4
A
B
With compass point on B and compass width equal to the third length given, draw another arc that intersects the arc from step 3. Label the intersection point C.
C
A 5
B
Using a ruler or straight edge, join Ato Cand Bto Cto produce the required triangle.