The selling price of a refrigerator is $521.25. if the markup is 25% of the dealers cost, what is the dealers cost of the refrigerator

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

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

Ineed with number 6 , explain how to get 1978