Question

Find the length of LA
Triangle proportionality

Answer 1

15

Explanation:

4 x __ = 12

the blank would be 3, once you did it on one side you have to do it on the other side too

5 x 3 = 15

Another way you can do it is by...

`(4)/(12)` =
`(5)/(x)`

solve for x (cross multiply)

Answer 2

15

Explanation:

CO : CL = OR : LA

* substitute the side letters with the given side lengths *

( let AL = x )

4 : 5 = 12 : x or

`(4)/(5) =(12)/(x)`

now we solve for x by cross multiplying

4 * x = 4x

12 * 5 = 60

now we have 4x = 60

step 2 divide each side by 4

4x / 4 = x

60 / 4 = 15

we're left with x = 15

hence LA = 15