Please help me solve this problem?

Question

V27 - V147 =

Answer 1

Assuming that 27 and 147 are coefficients and not indices:
V(27 - 147) = -120 V,
or, written in the same manner as the question,
V27 - V147 = -V120.

Answer 2

√27 - √147
= √(9 x 3) - √(49 x 3)
= 3.√3 - 7.√3
= - 4.√3

Answer 3

√27 - √147


prime factor
√(3 x 3 x 3) - √(3 x 7 x 7)

√(3^2 x 3) - √(7^2 x 3)

3√(3) - 7√(3)

-4√(3)