A linear sequence starts, a + 2b, a + 6b, a + 10b …….. …….. The 2nd term has value 8. The 5th term has value 44. Work out the values of a and b

As it states that it is a "linear" sequence. You can identify the pattern and recognise that the 4th and 5th terms will be, a+14b and a+18b respectively.As the 2nd term has the value 8. This means that a+6b=8. This alone is not enough to answer the question.The 5th term that we had worked out in step 1 is equal to 44 as stated in the question. Therefore, a+18b=44.You can now create a simultaneous equation. Structure the two equations adjacent to each other for the easiest way to look at it.a+6b=8 and a+18b=44. You can now cancel out the a's by subtracting the one equation from the other. It will be easier to subtract the smaller numbers from the larger numbers.Therefore, a-a=0. 18b-6b=12b. And 44-8=36.Therefore, 12b=36. b=3. This can be substituted back into either of the previous equation. In this case, we will use the easier equation for substitution which is, a+6b=8.Therefore, a+ 6(3)=8. a+18=8. Therefore, a= -10 b= 3

Answered by Haris A. Maths tutor

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