Question

Can someone help explain ??? Please

Answer 1

x = 6

Explanation:

Look at the picture.

ΔADC and ΔCDB are similar (AA). Therefore the sides are in proportion:

`(AD)/(DC)=(DC)/(DB)`

We have

`AD=9,\ DC=x,\ DB=4`

Substitute:

`(9)/(x)=(x)/(4)` cross multiply

`x^2=(9)(4)\\\\x^2=36\to x=√(36)\\\\x=6`