Q. Find one value of x that is a solution to the equation:(x2−7)2+2x2−14=0x=□
Expand and combine terms: We are given the equation [(x2−7)2+2x2−14=0]. Let's first expand the squared term and then combine like terms.[(x2−7)2] becomes x4−14x2+49. So the equation becomes x4−14x2+49+2x2−14=0.
Simplify the equation: Combine the x2 terms and the constant terms.[x4−14x2+2x2] becomes [x4−12x2].[49−14] becomes [35].So the equation now is [x4−12x2+35=0].
Substitute and factor: This is a quadratic equation in terms of x2. Let's substitute y for x2, so we have [y2−12y+35=0].Now we need to factor this quadratic equation.
Find possible solutions for : We are looking for two numbers that multiply to and add up to −12-12−12. These numbers are −5-5−5 and −7-7−7.\newlineSo we can write the factored form as [(y - 555)(y - 777) = 000].
Solve for x in each case: Now we have two possible solutions for y: y=5y = 5y=5 or y=7y = 7y=7.\newlineRemember that y was a substitute for x2x^2x2, so we now have x2=5x^2 = 5x2=5 or x2=7x^2 = 7x2=7.
Final solutions: We will solve for xxx in each case. Starting with x2=5x^2 = 5x2=5, we take the square root of both sides to get x=5x = \sqrt{5}x=5 or x=−5x = -\sqrt{5}x=−5.
Final solutions: We will solve for x in each case. Starting with x2=5x^2 = 5x2=5, we take the square root of both sides to get x=5x = \sqrt{5}x=5 or x=−5x = -\sqrt{5}x=−5.Now we solve x2=7x^2 = 7x2=7 by taking the square root of both sides to get x=7x = \sqrt{7}x=7 or x=−7x = -\sqrt{7}x=−7.
Final solutions: We will solve for x in each case. Starting with x2=5x^2 = 5x2=5, we take the square root of both sides to get x=5x = \sqrt{5}x=5 or x=−5x = -\sqrt{5}x=−5. Now we solve x2=7x^2 = 7x2=7 by taking the square root of both sides to get x=7x = \sqrt{7}x=7 or x=−7x = -\sqrt{7}x=−7. We have found four possible values for x: 5\sqrt{5}5, −5-\sqrt{5}−5, 7\sqrt{7}7, −7-\sqrt{7}−7. We can choose any one of these as a correct solution to the original equation.
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