document.write( "Question 640197: Solve for X: √(X+5)=X-1
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document.write( "(√(X+5))^2=(X-1)^2
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document.write( "X+5=X^2-2X+1
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document.write( "X^2-3X-4=0
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Algebra.Com's Answer #403058 by josh_jordan(263)![]() ![]() You can put this solution on YOUR website! Almost there! :) Last line says: \n" ); document.write( "\n" ); document.write( "We can solve for x in 3 different ways: factoring, completing the square, or using the quadratic formula. The easiest of these ways is factoring, so let's see if we can factor this equation.\r \n" ); document.write( "\n" ); document.write( "Let's look at the number at the end of the left side of the equal sign: -4 \n" ); document.write( "Now let's look at the middle number/variable: -3. \n" ); document.write( "For us to be able to solve by factoring, we need to have 2 numbers that multiply together to equal -4 AND can be added together to equal -3. Let's look at the products of -4:\r \n" ); document.write( "\n" ); document.write( "-1 x 4 = -4 \n" ); document.write( " 1 x -4 = -4 \n" ); document.write( " 2 x -2 = -4 \n" ); document.write( "-2 x 2 = -4\r \n" ); document.write( "\n" ); document.write( "Now, let's add each of these products to see if they equal -3:\r \n" ); document.write( "\n" ); document.write( "-1 + 4 = 3 \n" ); document.write( " 1 + -4 = -3\r \n" ); document.write( "\n" ); document.write( "We can stop right there, because 1 + -4 = -3\r \n" ); document.write( "\n" ); document.write( "So, \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "AND \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "To find out if both of these numbers are solutions, we will substitute x in our original equation for each of our possible solutions:\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since 2 does NOT equal -2, we know that -1 is NOT a solution\r \n" ); document.write( "\n" ); document.write( "Now let's try 4:\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since both sides of the equal sign are the same, 4 IS a solution. \r \n" ); document.write( "\n" ); document.write( "FINAL ANSWER: x = 4 \n" ); document.write( " |