Two parallel lines are cut by a transversa

What number should be added to both sides of the equation to complete this square? x^2-10x=7

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?

Im gonna fail 7th grade selective breeding 1. creates offspring which are genetically identical to the parent 2. is the process of breeding only organisms with desirable traits 3. involves the removal of the nucleus of a cell 4. combines traits from organisms of different species