Answer:
x = 3/2 or 0
Explanation:
let the number be x
"4 times a number" : 4x
"4 times a number is decreased by 3" : 4x -3
"this difference is squared" : (4x -3)²
"the result is 9" : (4x -3)² = 9 (solve this equation for x)
(4x -3)² = 9 (square root of both sides)
4x-3 = ±√9
4x-3 = ±3 (add 3 to both sides)
4x = ±3 + 3
Hence
4x = 3 + 3 = 6 ====> x = 6/4=3/2
or
4x = -3 + 3 = 0 ====> x = 0