I'm assuming that the number after the variable is supposed to be the exponent.

Combine like terms to get:
K Value is a steady state of the heat flow through a unit area of a homogeneous material induced by the unit temperature gradient. It can be determined by the flow of heat from a hotter surface to a colder surface. It is used to describe British thermal unit (BTU) per hour
If we are supposed to assume that QS=TV
4v+3=7v-9
minus 4v both sides
3=3v-9
add 9
12=3v
divide 3
4=v
v=4
sub back
4v+3=QS=TV
4(4)+3=QS=TV
16+3=QS
19=QS=TV
then answer is C