Answer:
The unknown number is -3
Explanation:
Represent unknown as x
Write as an equation
12 + (x * 5) = -3
Multiply
12 + 5x = -3
Subtract -5x from both sides of the equation
12 = -3 - 5x
Add 3 to both sides of the equation
15 = -5x
Divide both sides by -5
x = -3
The unknown number is -3
Hope this helps :)