hey heres a few math quest i need to have for test review please help
1.) 2x²-36=x
2.) 5x²+9x=-4
3.) k²-31-2k=-6-3k²-2k
4.) 9n²=4+7n
5.) 8n²+4n-16=-n2
6.) 8n²+7n-15+-7
thank you in advance also we are talking about quadratic equations
1.) 2x²-36=x
2.) 5x²+9x=-4
3.) k²-31-2k=-6-3k²-2k
4.) 9n²=4+7n
5.) 8n²+4n-16=-n2
6.) 8n²+7n-15+-7
thank you in advance also we are talking about quadratic equations
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First, add spaces so that things are more readable. The space bar is the biggest key on the keyboard as it should be used the most.
2x² - 36 = x
2x^2 - x - 36 = 0
need factors of 2 (2 and 1) and 36 (1, 36; 2, 18; 3, 12; 4, 9; 6, 6) that when multiplied by 2 and 1 will subtract (negative on the 36) to -1
(2x - ?)(x + ?) or swap the + and -
notice that with the 4 and 9, that multiplying the 4 by 2 we get 8 which is one less than 9
(2x - 9)(x + 4)
multiply it out to verify
2x^2 - 9x + 8x - 36 = 2x^2 - x - 36 so all is good
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work the rest like the one above.
2x² - 36 = x
2x^2 - x - 36 = 0
need factors of 2 (2 and 1) and 36 (1, 36; 2, 18; 3, 12; 4, 9; 6, 6) that when multiplied by 2 and 1 will subtract (negative on the 36) to -1
(2x - ?)(x + ?) or swap the + and -
notice that with the 4 and 9, that multiplying the 4 by 2 we get 8 which is one less than 9
(2x - 9)(x + 4)
multiply it out to verify
2x^2 - 9x + 8x - 36 = 2x^2 - x - 36 so all is good
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work the rest like the one above.