Could someone show me how to get the work for:

3/4 (sqrt)-16/25 ?

The answer says 3/5i.
Could anybody tell me how to get there and work with complex fractions and simplify them? Thanks!

3/4 SQRT(-16/25)
3/4 SQRT( 16/25*-1)
3/4 *4/5 *SQRT( -1)
but the sqrt of -1 is defined as i, so
3/4 *4/5 *SQRT( -1)=
3i/5

i did this the first time, but was like... no that's not right. i feel quite dumb.
ahhh.. thank you so much!

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