document.write( "Question 1203773: f(x) = x^2 + 5\r
\n" ); document.write( "\n" ); document.write( "a) f(-6) =\r
\n" ); document.write( "\n" ); document.write( "b) Find if f(x) = 14\r
\n" ); document.write( "\n" ); document.write( "c) f(x + h) =\r
\n" ); document.write( "\n" ); document.write( "d) Calculate: f(x + h) - f(x) over h\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Can you please explain to me this homework question by showing the step-by-step calculations? Thank you!
\n" ); document.write( "

Algebra.Com's Answer #839604 by mananth(16946)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "a) find f(-6), plug -6 into the function \r
\n" ); document.write( "\n" ); document.write( "f(-6) = (-6)^2 + 5
\n" ); document.write( "f(-6) = 36 + 5
\n" ); document.write( "f(-6) = 41\r
\n" ); document.write( "\n" ); document.write( "b) f(x) = 14, find x:\r
\n" ); document.write( "\n" ); document.write( "14 = x^2 + 5\r
\n" ); document.write( "\n" ); document.write( "Subtract 5 from both sides:\r
\n" ); document.write( "\n" ); document.write( "x^2 = 14 - 5
\n" ); document.write( "x^2 = 9\r
\n" ); document.write( "\n" ); document.write( " take the square root of both sides:\r
\n" ); document.write( "\n" ); document.write( "x = ±sqrt(9)
\n" ); document.write( "x = ±3\r
\n" ); document.write( "\n" ); document.write( "So, x = 3 and x = -3.\r
\n" ); document.write( "\n" ); document.write( "c) To find f(x + h), you plug x + h for x:\r
\n" ); document.write( "\n" ); document.write( "f(x + h) = (x + h)^2 + 5\r
\n" ); document.write( "\n" ); document.write( "d) We know f(x+h) and f(x) from above\r
\n" ); document.write( "\n" ); document.write( "\"%28%28f%28x+%2B+h%29+-+f%28x%29%29%29%2Fh+\"= \"%28%28x+%2B+h%29%5E2+%2B+5+-+%28x%5E2+%2B+5%29%29%2Fh\"\r
\n" ); document.write( "\n" ); document.write( " simplify the R H S\r
\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+h%29%5E2+%2B+5+-+%28x%5E2+%2B+5%29%2Fh\"\r
\n" ); document.write( "\n" ); document.write( " = \"%28%28x%5E2+%2B+2xh+%2B+h%5E2+%2B+5%29+-+%28x%5E2+%2B+5%29%29%2Fh\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " cancel x^2 and -x^2 we get\r
\n" ); document.write( "\n" ); document.write( "\"%282xh+%2B+h%5E2%29%2Fh\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "h(2x + h)/h\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So,\"+%28f%28x+%2B+h%29+-+f%28x%29%29%2Fh+=+2x+%2B+h.\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );