Question

What is the common difference of the AP 5,9,13,17
If a=1 b=8 and c=15 find the value of b²-4ac
I i get two questions correct answer i will mark them as brainliest

Answer 1

Step-by-step explanation:

$ap : \: \: 5, \: 9, \: 13, \: 17 \\ a_{1} = 5 \: a_{2} = 9 \\ common \: difference \: (d) = a_{2} - a_{1} \\ = 9 - 5 = 4 \\ \\ a = 1, \: b = 8, \: c = 15 \\ {b}^{2} - 4ac = {8}^{2} - 4 \times 1 \times 15 \\ = 64 - 60 \\ = 4$

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please mark as Brainliest

Answer 2

Step-by-step explanation:

$A. \: P. = 5, \: \: 9, \: \: 13, \: \: 17 \\ Common \: \: Difference \\ = T_{2} - T_{1} \\ = 9 - 5 \\ = \: \underline{ \underline{4}} \\ \\ a = 1 \: \: \: \: b = 8 \: \: \: \: c = 15 \\ {b}^{2} - 4ac \\ = {8}^{2} - 4(1)(15) \\ = 64 - 60 \\ = \: \underline{ \underline{4}}$