Solve the equation by completing the square. (step by step please)

4x(x + 6) = -40

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.

Each unit cost 14p, how much would 942 units cost?

The bottom of a vase is a square.each side measury y+11 units.the square has a perimeter of 55 units what is the value of y?