If triangle abc is equilateral then triangle qrs is equilateral if triangle qrs is equilateral then triangle xyz is equilateral you can conclude that if triangle abc is equilateral then triangle xyz is equilateral?
law of detachment or law of syllogism?

Law of syllogism

Step-by-step explanation:

The law of syllogism says that it is a valid and true argument form of deductive logic.

In law of syllogism, there are three statements :

1. 1st Statement : If statement a, then statement b

2. 2nd Statement  : If statement b, then statement c

3. 3rd Statement  : If statement a, then statement c

Statements 1 and statement 2 is known as the premises of the argument. If the statements 1 and 2  are true, then the statement 3 must be the valid conclusion.

Therefore we can conclude that

1st Statement : If triangle abc is equilateral,(a) then triangle qrs is  equilateral, (b).

2nd Statement : If triangle qrs is equilateral,(b) then triangle xyz is equilateral,(c).

3rd Statement : If triangle ABC is equilateral,(a) then triangle xyz is equilateral,(c).

Thus this concludes that it is a law of syllogism.

so, converting firstly the mixed fractions to improper fractions and then "adding".