Question

x
$x \3 + 3 \x = 15 \x$
​

Answer 1

Answer:

x + 3 = 15

x = 15 - 3

x = 12

This is called transposition method. We carry the constant to the other side so that only the variable would be on the RHS or LHS side. When we transport a number, its sign changes.

+ to -

- to +

÷ to ×

× to ÷