Question

If A= 3i+4j & B= 7i+24j the vector having same magnitude as B & parallel to A is
?

Answer 1

The vector must be parallel to A and having magnitude equal to B  will be magnitude of B x UNIT VECTOR OF A

the magnitude of A = √(3^2 + 4^2) = √25 = 5 

hence the unit vector of A =(A vector) / lAl = 3i + 4j / 5
now magnitude of B = √(7^2 + 24^2) = 25

hence 25 x unit vector of A
          25 x (3i + 4j / 5)
       = 5(3i + 4j)

i hope it will help you 
regards