Answer:
The solution set is {-2, 2}
Explanation:
Although I recognize your "x2" as an effort to represent "the square of x," this really should be x^2 or x².
Solve x^2 + 3 = 7 for x:
First isolate x^2; do this by subtracting 3 from both sides, obtaining x^2 = 4.
Next, take the square root of both sides of x^2 = 4:
x = ±√4 = ±2
The solution set is {-2, 2}