2 5 x 10 15 July 8, 2019 16 32 64 128 Solve x 15 10 2 5 7 5 x )- 2 x 10 )= 15 5 x 6 )- 2 x 10 )= 15 5 (- 2 15 )- x =- 3 10 4x 5 x x 10 15 2 3x 2 5 x 1 3 4x 3 15 10 15 7 5 x 10 72 2 4 2 x 2 5 2 5 x 15 2 5 × 15 2 x 10 5