Solve 2x2 + 3x - 7 = x2 + 5x + 39 for x.
Solution:
Given, 2x2 + 3x - 7 = x2 + 5x + 39.
We have to solve for x.
By grouping of common terms,
2x² - x² + 3x - 5x - 7 - 39 = 0
(2 - 1)x² + (3 - 5)x - 46 = 0
x² - 2x - 46 = 0
Using quadratic formula,
x = -b ± √(b² - 4ac) / 2a
Here, a = 1, b = -2 and c = -46
x = -(-2) ± √((-2)² - 4(1)(-46)) / 2(1)
= 2 ± √ (4 + 4(46)) / 2
= 2 ± √4(1 + 46) / 2
= 2 ± 2√47 / 2
= 2(1 ± √47) / 2
= 1 ± √47
x = 1 + √47 and 1 - √47
Therefore, the value of x is 1 + √47, 1 - √47.
Solve 2x2 + 3x - 7 = x2 + 5x + 39 for x.
Summary:
2x2 + 3x - 7 = x2 + 5x + 39 for x = 1 + √47, 1 - √47.
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