document.write( "Question 54415: -x^2 > or = 9x+14 Please help!! I have to solve and show the solution in interval and algebraic form. I got through most of the problem but need help with the notation, and also want to confirm that I solved it right. -x^2-9x-14 > or = 0 factored is (-x-2)(x+7) so I got x= -2 and x= -7 as test points and by testing the regions on the number line, I found that -1 through +infinity does not work in the original problem. Im not sure where to go from here or how the interval notation should look. Thanks, Angela \n" ); document.write( "
Algebra.Com's Answer #36674 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! (-x-2)(x+7)>=0 so I got x= -2 and x= -7 \n" ); document.write( "Draw a number line. \n" ); document.write( "Put -7 and -2 on the line \n" ); document.write( "Test numbers in each of the three intervals: \n" ); document.write( "Interval (-inf,-7]; try -10; (10-2)(-10+7)<0 \n" ); document.write( "So, only x=-7 is a solution in this interval. \n" ); document.write( "Interval (-7,-2]; try -5; (5-2)(-5+7)>0; \n" ); document.write( "All x in this interval are part of the solution. \n" ); document.write( "Interval (-2,+inf); try 10: (-10-2)(10+7)<0 \n" ); document.write( "So no solutions in this interval. \n" ); document.write( "SOLUTION: \n" ); document.write( " -7<=x<=-2 \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " |