How is addition or subtraction of radicals related to other concepts of radicals?​

Xto the second power plus 14x plus 48. what are the factors? we are doing factoring trinomials with a=1

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

Some boys and girls were asked if they had a pet. one third of the group were boys. there were 20 boys. 20% of the girls had a pet. boys with a pet : girls with a pet = 1 : 5 i need to know how many girls there are.