Find AB
please help :-)
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Answer:
Therefore,
l(AB) = 15 units
Step-by-step explanation:
Given:
AD = DC
angle DBA = angle DBC = 90°
AB = 5x
CB = 4x - 3
To Find:
AB = ?
Solution:
In Δ ABD and Δ CBD
AD ≅ DC ……….{Given}
∠ DBA ≅ ∠ DBC …………..{measure of each angle is 90° given}
DB ≅ DB ....……….{ Reflexive property}
Δ ABD ≅ Δ CBD ..........….{By Hypotenuse Leg Theorem}
∴ AB ≅ CB ..............{corresponding sides of congruent triangles}
on substituting the values we get
[tex]5x=4x+3\\\\5x-4x=3\\\\\therefore x =3[/tex]
Now we require AB
[tex]AB=5x\\\\AB=5\times 3\\\\AB=15\ units[/tex]
Therefore,
l(AB) = 15 units