Question

Find ABplease help :-)​

Answer 1

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

$5x=4x+3\\\\5x-4x=3\\\\\therefore x =3$

Now we require AB

$AB=5x\\\\AB=5\times 3\\\\AB=15\ units$

Therefore,

l(AB) = 15 units