If using the method of completing the square to solve the quadratic equation X^2-10x+21=0

Afactory adds 3 red drops and 2 blue drops of coloring to white paint to make each pint of purple paint. the factory will make 50 gallons of the purple paint.how many drops of red and blue coloring will the factory need in the 50 gallon batch of purple paint.

Benjamin believes that ¼ % is equivalent to 25%. is he correct? why or why not?

Can someone me with these questions? ?