Respuesta :
Answer: [tex]P\triangle ADH = (a+b+\sqrt{a^2+b^2} )[/tex] unit
Step-by-step explanation:
Since Here Δ ABC is a isosceles triangle.
Also, [tex]AH\perp BC[/tex] and [tex]HD\perp AC[/tex]
Thus, ∠ ADH = 90°
That is, Δ ADH is the right angle triangle.
In which, AD = a unit and HD = b unit
And, By the definition of Pythagoras theorem,
[tex]AH^2 = HD^2 + AD^2[/tex]
⇒ [tex]AH^2 = a^2 +b^2[/tex]
⇒ [tex]AH = \sqrt{a^2+b^2}[/tex]
Since, the perimeter of a triangle = sum of the all sides of the triangle.
Therefore, perimeter of ΔADH = AD + DH + AH
= [tex]a + b + \sqrt{a^2+b^2}[/tex] unit
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Answer:
3a+b
Step-by-step explanation:
Statement-Reasoning Format:
1. CB is base- Given
2. △ABC – isos. △- Given
3. AC=CB- Def. of isos. △
4. AH is an altitude, median, and angle bisector- Def. of alt. med., ∠ bisect. in isos. △
5. m∠BAC= 120°- Given
6. m∠DAH=m∠BAH=m∠BAC/2=120/2=60°-Def of ∠ bisect.
7. 180°-m∠CDH=m∠HDA=180-90=90°-Linear Pair
8. m∠DHA=180- (m∠HDA+m∠HAD)= 180-(90+60)=180-150=30°-Sum of ∠s in a △
9. AD=a cm-Given
10. HA=2AD=2(a)=2a cm- Leg Opposite to 30°
11. HD=b cm- Given
12. P△ADH=a+2a+b= 3a+b cm-Part Whole Postulate
Hope This Helps!