Question
Find the value of each unknown:
k + 8 = 12 – k
k + 8 = 12 – k
✓
Answer
k + 8 = 12 – k
Add k on both sides
k + 8 + k = 12 – k + k
⇒ 2k + 8 = 12
Subtract 8 from both sides
2k + 8 – 8 = 12 – 8
⇒ -2k = 4
Divide both sides by 2
$\frac{2 k}{2}=\frac{4}{2}$
⇒ k = 2
Add k on both sides
k + 8 + k = 12 – k + k
⇒ 2k + 8 = 12
Subtract 8 from both sides
2k + 8 – 8 = 12 – 8
⇒ -2k = 4
Divide both sides by 2
$\frac{2 k}{2}=\frac{4}{2}$
⇒ k = 2
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