Answer:
because logarithmic is inverse of exponential equations
531441
Step-by-step explanation:
x=1
8x+6+2x=12+4x
10x+6=12+4x
-6 -6
10x=6+4x
-4x -4x
6x=6
6 times 7 =42
5 times 7 =45
42 + 45 = 87