4x^2+7x=0 how do i factor this equasion

What are correct trigonometric ratios that could be used to determine the length of ln

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle