Answer:
x=126
Step-by-step explanation:
let 'x' represent the unknown number
(2/7)x + 9 = 45
Subtract 9 from both sides
2/7x=36
Because the fraction is being multiplied by 'x' we can multiply both sides by its reciprocal (because a fraction multiplied by its reciprocal is 1 which would 'eliminate' it from the left side therefore isolating 'x').
x=126