Solve this equation 90x-60y is equal to 68 and 90x-70y is equal to 91

Mathematics

2 answers:

uranmaximum [27]4 years ago

5 0

X=-7/9

Thanks so much

Tanzania [10]4 years ago

3 0

Answer:

Step-by-step explanation:

90x - 60y = 68.....multiply by -1

90x - 70y = 91

---------------------------

-90x + 60y = -68 (result of multiplying by -1)

90x - 70y = 91

---------------------------add

-10y = 23

y = -23/10 <===

90x - 60y = 68

90x - 60(-23/10) = 68

90x + 138 = 68

90x = 68 - 138

90x = - 70

x = -70/90

x = -7/9 <=====

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MAXImum [283]

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Step-by-step explanation:

First of all, we have to determine if the given sequence is arithmetic sequence or geometric. For that purpose, we calculate the common difference and common ratio

Given sequence is:

11,4,-3,-10,-17...

Here

$a_1 = 11\\a_2 = 4\\a_3 = -3\\So,\\d = a_2 - a_1 = 4-11 = -7\\d = a_3-a_2 = -3-4 = -7$