If 8=10 and 1=7, which describes all the lines that must be parallel?

Lines r and s and lines t and u must be parallel.

Step-by-step explanation:

If which are alternate interior angle corresponding to line t and u.

then by Alternate interior angle property :

Lines t and u must be parallel.

If which are alternate exterior angle corresponding to line r and us.

then by Alternate exterior angle property :

Lines r and s must be parallel.

Hence, Lines r and s and lines t and u must be parallel.

agree

step-by-step explanation:

it will take 9 minutes