I have no clue if you can see this but help please

What is the missing constant term in the perfect square that starts with x^2 -20x

Sheila wants to bake six muffins but the recipe is for 12 muffins . this means you only need half of the ingredients listed how much of the of each ingredient does she need? one cup and banana chips ,7 tablespoons oil , two eggs, 3/4 cups flour 1/4 cup walnuts show all you work and justify your answer using a baby toulmin.

Molly shared a spool of ribbon with 12 people. each person received 3 feet of ribbon. which equation can she use to find r, the number of feet of ribbon that her spool originally had?