Question
Determine the value of a − b given that a + 3b = 18a
and 3a + b = 30 .Solution
Given: a + 3b = 18 ..... (I) And 3a + b = 30 ....... (II) On subtracting equation (I) from equation (II) , we have; 2a - 2b = 12 So, a - b = 6 Hence, option b.
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