Ruka hadi maudhui
The Lumenary
Darasa la 3–5Geometry & TopologyImepangwa

Area, perimeter and angles

Area as the number of unit squares that cover a shape, perimeter as the distance around it, area of rectangles, first volumes, and angles as amounts of turn measured in degrees.

math.geom.area-angles

Somo la mada hii bado halijaandikwa. Muhtasari ulio hapa chini ni sehemu ya ramani ya mtaala na haujakaguliwa.

Inajengwa juu ya

Masharti ya awali ya lazima 6 (hadi chini kabisa)

Utajifunza

  • Find areas by counting unit squares and by multiplying length by width, and compute perimeters.
  • Show that shapes with the same perimeter can have different areas, and vice versa.
  • Measure and draw angles in degrees, and classify triangles and quadrilaterals by their sides and angles.
  • Find the volume of a rectangular box by counting unit cubes.

Fasili

  • Area is the amount of surface a shape covers, measured in square units.
  • Perimeter is the total length of the boundary of a shape.
  • An angle is the amount of turn between two rays from a common point; a full turn is 360°.

Nadharia

  • The area of a rectangle is length × width.
  • The angles of a triangle in the plane add up to 180°.
  • The volume of a rectangular box is length × width × height.

Mawazo potofu ya kawaida

  • Confusing area with perimeter.
  • Thinking an angle gets bigger when its arms are drawn longer.
  • Believing that shapes with equal perimeters must have equal areas.

Inaelekea kwa

Ugunduzi wa hiari

  • Measure theory and integration Which sets of points have an area at all? Measure theory answers this; with the axiom of choice, some sets cannot be given a countably additive area that is unchanged by sliding them.

Njia za kujifunza

Usomaji zaidi

  • Paul Lockhart, Measurement (2012) — For teachers and curious adults.