document.write( "Question 1210429: 1) Solve 2(√4x+5) - (√3x+1) = 6, where x is an integer.\r
\n" ); document.write( "\n" ); 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)\"\" \"About 
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 \"2sqrt%284x%29%2B5\", when apparently the intended expression is 2(√(4x+5)) = \"2sqrt%284x%2B5%29\"

\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: \"169x%5E2-874x%2B145=0\"

\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

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