Transcript Lesson 1.5

Bellringer
• Sketch each figure
1.𝑪𝑫
2.𝑮𝑯
3.Acute ∠ABC
4.𝑨𝑩 ∥ 𝑺𝑻
1.5
Basic Constructions
Perpendicular Lines (Rectas Perpendiculares)
• two lines that intersect to form right angles.
The symbol ⊥ means “perpendicular to.”
• Las rectas perpendiculares son rectas que se
cortan y forman 𝐚ngulos rectos. El s𝑖mbolo ⊥
significa “es perpendicular a”
• m⊥l
Perpendicular bisector (Mediatriz)
• A line, segment, or ray that is perpendicular to
the segment at its midpoint, thereby bisecting
the segment into two congruent segments.
• La mediatriz de un segmento es una recta,
segmento, o rayo que es perpendicular al
segmento en su punto medio.
Angle bisector
• A ray that divides an angle into two congruent
coplanar angles. Its endpoint is at the angle vertex.
• La bisectriz de un 𝐚ngulo es un rayo que divide al
𝐚ngulo en dos 𝐚ngulos congruentes.
Finding angle measures
• 𝑨𝑩 bisects ∠𝑪𝑨𝑫 so that m∠𝑪𝑨𝑩 = 5x – 25 and
m∠𝑩𝑨𝑫 = 3x + 5. Solve for x and find the m∠𝑪𝑨𝑫.
Finding angle measures
• 𝑩𝑫 bisects ∠𝑨𝑩𝑪 so that m∠𝐴𝐵𝐷 = 𝑥 and
m∠𝐷𝐵𝐶 = 4x - 48. Solve for x and find the m∠𝐴𝐵𝐶.
Homework
• Pg. 37 #’s 9- 12
• Pg. 40 #’s 41 - 50