Answer:
B. 3x = 15
Explanation:
To find out which equation is the correct one, we just have to replace x with 5 for each one.
2 + x = 3
2 + 5 = 7
Since 2 + 5 is 7, this one is incorrect.
3 x 5 = 15
3 times 5 is 15, so B is correct. Let's try out the other ones anyway.
5 / 2 = 2.5
Incorrect.
5 - 7 = -2
Incorrect.
The only correct equation was B. 3x = 15