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Solve: 21 - 3(a - 7) = a + 20. The value of a is
Aa = 5.5
Ba = 11
Ca = 22
Da = 4
Answer & Solution
Correct answer: A. a = 5.5
1. Expand: 21 - 3 a + 21 = a + 20.
2. Combine: 42 - 3 a = a + 20, so 4 a = 22.
3. Divide by 4: a = 22/4 = 5.5.
4. Example 1 from the chapter.
_Source: Selina Concise Mathematics Class 8, Ch 18 Linear Equations in One Variable (Mistral OCR'd PDF), Example 1_
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