Answer :
Final answer:
To solve the word problem, use the equation x + 12 = 20 and subtract 12 from both sides to find the value of x. Kayla has already mailed 8 invitations for the pizza party.
Explanation:
To solve the word problem, we can use the equation x + 12 = 20, where x represents the number of invitations already mailed. By subtracting 12 from both sides of the equation, we can find the value of x. Thus, x = 20 - 12, which equals 8. Therefore, Kayla has already mailed 8 invitations for the pizza party.
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