In the image above, have 3 squares
A
B
E
F
,
D
C
F
G
and
C
D
G
H
. Find the sum of the angles
α
,
β
and
γ
. Put you answer in degree.
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F G A F = 2
A G A H = 5 1 0 = 2
A F F H = 2 2 = 2
△ A F H is similar to △ A F H then F A G = γ
β = G A C
α = F A E
α + β + γ = F A E + G A C + F A G = 9 0
∠ AGH = 45 (DIAGONALS BISECT THE ANGLES = 90/2).....
tan ∠ AFH= 1/2.....
tan ∠ AEH=1/3......
tan[ ∠ AFH+ ∠ AEH]= tan ∠ AFH+tan ∠ AEH/1-tan ∠ AFH tan ∠ AEH} = 1 − 1 / 2 ∗ 1 / 3 1 / 2 + 1 / 3 = 5 / 6 5 / 6 = 1........
So ∠ AFH+ ∠ AEH=45........
SO ∠ AGH+ ∠ AFH+ ∠ AEH = 45 + 45 = 9 0
Rearrange the triangles as shown. If we let the original square have a side length of
x
, we can get the lengths shown by given measurements, the Pythagorean Theorem, or the Distance Formula. Note that the quadrilateral satisfies the converse of Ptolemy's Theorem. Therefore, this quadrilateral is a cyclic quadrilateral, so the opposite angles add to
1
8
0
∘
. This gives
α
+
β
+
γ
+
9
0
∘
=
1
8
0
∘
α
+
β
+
γ
=
9
0
∘
.
Alpha=45 ......angle made by diagonal Tan(beta)=1/2 Tan (gamma)=1/3 Now use property, tan (A+B)=(tanA+tanB) /1-tanAtanB Get the answer
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