To determine which equation Soo-Jung solved using the subtraction property of equality, let's analyze each option step-by-step.
1. [tex]\(4y = 12\)[/tex]:
- To solve this equation for [tex]\(y\)[/tex], you would divide both sides by 4, not use subtraction.
- Dividing both sides gives [tex]\(y = \frac{12}{4} = 3\)[/tex].
2. [tex]\(\frac{y}{4} = 12\)[/tex]:
- To solve this equation for [tex]\(y\)[/tex], you would multiply both sides by 4, not use subtraction.
- Multiplying both sides gives [tex]\(y = 12 \times 4 = 48\)[/tex].
3. [tex]\(2(4y) = 12\)[/tex]:
- Simplifying the left side, it becomes [tex]\(8y = 12\)[/tex].
- To solve this equation for [tex]\(y\)[/tex], you would divide both sides by 8, not use subtraction.
- Dividing both sides gives [tex]\(y = \frac{12}{8} = \frac{3}{2}\)[/tex].
4. [tex]\(y + 4 = 12\)[/tex]:
- To solve this equation for [tex]\(y\)[/tex], you would use the subtraction property of equality.
- Subtracting 4 from both sides gives [tex]\(y = 12 - 4 = 8\)[/tex].
From the analysis above, the equation that Soo-Jung could have solved using the subtraction property of equality is:
[tex]\[ y + 4 = 12 \][/tex]
Thus, the correct equation is:
[tex]\[ \boxed{y + 4 = 12} \][/tex]
