Question 431547
1)   5/sqrt7

HINT: Multiply this fraction by [sqrt(7)]/[sqrt(7)]

ANSWER: (5[SQRT(7)])/7

2)   7/(sqrt7 + sqrt3)

HINT: Multiply this fraction by [sqrt(7)- sqrt(3)]/[sqrt(7)+ sqrt(3)]

ANSWER: 7*(sqrt(7)-sqrt(3))/4