ABC is an equilateral triangle P and Q are points of lines AB and AC respectively such that PQ II BC. If PQ = 5cm, then the area of triangle APQ is?
Answers
Answer:
25 cm²
Step-by-step explanation:
Here PQ | | BC , So
In ∆ ABC and ∆ APQ
∠ ABC = ∠APQ ( As We know PQ | | BC and take AB as transversal line so these angles are corresponding angles )
∠ ACB = ∠AQP ( As We know PQ | | BC and take AC as transversal line so these angles are corresponding angles )
So,
∆ ABC ~ ∆ APQ ( By AA rule )
So, we can say that
Area of ∆ ABCArea of ∆ APQ = (Corresponding side )2(Corresponding side )2So,⇒Area of ∆ APQ = (PQ )2⇒Area of ∆ APQ = (5 )2⇒Area of ∆ APQ =25 cm2 (Ans)
GIVEN :-
- ABC is an equilateral triangle .
- P and Q are points of lines AB and AC respectively such that PQ II BC. If PQ = 5cm.
TO FIND :-
- The area of Δ APQ.
SOLUTION :-
Since, the Δ is an equilateral so AB = BC = AC.
Now from mid point theoren we have,
➳ 2PQ = BC
➳ 5 * 2 = BC
➳ 10 cm = BC
Since, the Δ is an equilateral so AB = BC = AC = 10 cm.
Also,
➳ AP = AQ = 10/2 cm.
➳ AP = AQ = 5 cm.
Now in Δ APQ we have
- AP = AQ = PQ = 5 cm [ Hence Δ APQ ia also an equilateral traingle ]
Now as we know that,
➳ Area of triangle = √3/4 * ( side )²
➳ Area of triangle = √3/4 * ( 5 )²
➳ Area of triangle = 25 * √3/4
➳ Area of triangle = ( 25√3 )/4 cm².
Hence The area of Δ APQ is ( 25√3 )/4 cm².