Math - 2019-20
G.4abcdef - Basic Constructions
G.4 The student will construct and justify the constructions of
a) a line segment congruent to a given line segment;
b) the perpendicular bisector of a line segment;
c) a perpendicular to a given line from a point not on the line;
d) a perpendicular to a given line at a given point on the line;
e) the bisector of a given angle;
f) an angle congruent to a given angle;
BIG IDEAS
- I can design and draft house plans, lay out the bases for a
baseball diamond, determine safe construction with adequate support and stress
beams, create pleasing patterns for trendy fashions, animate characters for a
feature movie, and program a popular computer game.
- I will
better understand geometric concepts,
the validation of proofs, and the requirement of critical thinking and I will be
able to make drawings when direct measurement is not possible or appropriate.
UNDERSTANDING THE STANDARD
· Construction techniques are used to solve practical problems in engineering, architectural design, and building construction.
· Construction techniques include using a straightedge and compass, paper folding, and dynamic geometry software.
· Geometric constructions assist in justifying, verifying, and visually reinforcing geometric relationships.
· There are multiple methods to most geometric constructions. Students would benefit from experiences with more than one method and should be able to justify each step of geometric constructions.
· Individual steps of constructions can be justified using angle relationships, properties of quadrilaterals, congruent triangles, and/or circles.
The construction for a line segment congruent to a given line segment can be justified using properties of a circle.
The construction for the perpendicular bisector of a line segment can be justified using the properties of quadrilaterals or congruent triangles.
The constructions for a perpendicular to a given line from a point on, or not on, the line can be justified using the properties of quadrilaterals or congruent triangles.
The constructions for the bisector of a given angle and an angle congruent to a given angle can be justified using the properties of quadrilaterals or congruent triangles.
The construction for a line parallel to a given line through a point not on the line can be justified using the angle relationships formed when two lines are intersected by a transversal.
The constructions for an equilateral triangle, square, or regular hexagon inscribed in a circle can be justified using properties of circles.
· Constructions can be completed within the context of complex figures.
ESSENTIALS
The student will use problem solving, mathematical communication, mathematical reasoning, connections, and representations to
· G.4a1 Construct and justify the constructions of a line segment congruent to a given line segment;
·
G.4b1 Construct
and justify the constructions of the
perpendicular bisector of a line segment;
·
G.4c1 Construct
and justify the constructions of a perpendicular
to a given line from a point not on the line;
·
G.4d1 Construct
and justify the constructions of a
perpendicular to a given line at a given point on the line;
·
G.4e1 Construct
and justify the constructions of the
bisector of a given angle;
· G.4f 1 Construct and justify the constructions of an angle congruent to a given angle;
KEY VOCABULARY
construct,
justify, construction, line segment, perpendicular, perpendicular bisector, line, point,
bisector, angle, congruent, equilateral triangle, square, regular, hexagon,
circle, circumscribed, tangent, tangent line, straightedge/ruler, compass