document.write( "Question 1210429: 1) Solve 2(√4x+5) - (√3x+1) = 6, where x is an integer.\r
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document.write( "2) Given that sinx = -3/5, where 180° ≤ x ≤ 270° and cos y = - 15/17 , where 90° ≤ y ≤ 180°. find the value of tan(x-y).
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Algebra.Com's Answer #852516 by greenestamps(13250) You can put this solution on YOUR website! \n" ); document.write( "For the first problem.... \n" ); document.write( "NOTE: Don't use \"√\" when posting problems involving square roots -- or, if you do, enclose the expressions under the radicals in parentheses. \"2(√4x+5)\" looks like \n" ); document.write( "Outline for a formal solution.... \n" ); document.write( "(1) rewrite the equation with one radical on each side \n" ); document.write( "(2) square both sides of that equation; you will still have a radical on one side \n" ); document.write( "(3) isolate that radical on one side and again square both sides of the equation, resulting finally in an equation without any radicals \n" ); document.write( "If you do all that algebra correctly, you will end up with this quadratic equation: \n" ); document.write( "Options for what to do from here.... \n" ); document.write( "(1) solve that equation by factoring (have fun!!!) \n" ); document.write( "(2) solve the equation using the quadratic formula (perhaps even MORE fun!!!!) \n" ); document.write( "(3) solve the equation using a graphing calculator (e.g., TI84 or equivalent; or online at desmos.com) \n" ); document.write( "Option (3) is much less work than either of the other options.... \n" ); document.write( "But if you are going to solve the problem using technology, why bother with the algebra outlined above? Simply use a graphing utility to graph the expressions on each side of the original equation and find the x value where the graphs intersect. \n" ); document.write( "Finally, what is the easiest (and by far the fastest) way to solve the problem? \n" ); document.write( "Assume the answer is a whole number; ignore ALL of the above and look for whole number values of x for which (4x+5) and (3x+1) are both perfect squares. \n" ); document.write( "ANSWER: x = 5 \n" ); document.write( "CHECK: 2*sqrt(4x+5)-sqrt(3x+1) = 2*sqrt(25)-sqrt(16) = 2(5)-4 = 10-4 = 6 \n" ); document.write( " \n" ); document.write( " |