Question

Find AB

please help :-)​

Answer 1

Therefore,

l(AB) = 15 units

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* 3\\\\AB=15\ units`

Therefore,

l(AB) = 15 units