solve 19 question........
Answers
Answer:
108cm²
Step-by-step explanation:
hypotenuse =15cm
base =9cm
perpendicular =
h²=p²+b²
15²=p²+9²
225=p²+81
p²=144
p=12
the area of triangle =1/2×base×height
=1/2×18×12
=108cm²
⟼ Let ABC be the given isoceles traingle
⟼ AB= AC= 15cm
⟼ AD ⊥ BC and its bisector BC.
BD=DC= 9cm
⟼ By Phthagores theoram:-
(AB)²= (BD)²+(AD)²
15²= 9²+(AD)²
(AD)²= 225-81
(AD)²= 144
AD= 12
⟼ Area of traingle:- 1÷2×b×h
1÷2×18×12
108 cm²
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So the area of Isoceles traingle is:- 108cm².
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Some Important Formulae:-
⟼ Area of rectangle= Length×Breadth
⟼ Length of a rectangle= Area÷Breadth
⟼ Breadth of a rectangle= Area÷Length
⟼ Area of a square= s×s
⟼ Side of a square= √Area
⟼ Area of a parallelogram= Base×Height
⟼ Area of a traingle= 1÷2×base×height
⟼ Area of an equilateral triangle= √3a²÷4
⟼ Area of a trapezium= 1÷2× height× sum of parallel sides
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