Solve by completing the square.f2+18f−19=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.f= _____ or f= _____
Q. Solve by completing the square.f2+18f−19=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.f= _____ or f= _____
Rewrite in standard form:f2+18f−19=0Rewrite the equation in the form of x2+bx=c.Add 19 to both sides.f2+18f−19+19=0+19f2+18f=19
Complete the square:f2+18f=19Choose the equation after completing the square.Since (218)2=81, add 81 to both sides.f2+18f+81=19+81f2+18f+81=100
Factor left side:f2+18f+81=100 Identify the equation after factoring the left side. f2+18f+81=100(f+218)2=100(f+9)2=100
Take square root:f+9)2=100(Identify the equation after taking the square root on both sides.Take the square root of both sides of the equation.\$\sqrt{(f + 9)^2} = \sqrt{100}\)\(\newline\)\(f + 9 = \pm\sqrt{100}\)\(\newline\)\(f + 9 = \pm10\)
Isolate variable: We found:\(\newline\)\(f + 9 = \pm10\)\(\newline\)Choose the equation after isolating the variable \(f\).\(\newline\)To isolate \(f\), subtract \(9\) from both sides of the equation.\(\newline\)\(f + 9 - 9 = \pm10 - 9\)\(\newline\)\(f = -9 \pm 10\)
Isolate variable: We found:\(\newline\)\(f + 9 = \pm10\)\(\newline\)Choose the equation after isolating the variable \(f\).\(\newline\)To isolate \(f\), subtract \(9\) from both sides of the equation.\(\newline\)\(f + 9 - 9 = \pm10 - 9\)\(\newline\)\(f = -9 \pm 10\)We have:\(\newline\)\(f = -9 \pm 10\)\(\newline\)What are the two values of \(f\)?\(\newline\)\(f = -9 + 10\) implies \(f = 1\).\(\newline\)\(f\)\(0\) implies \(f\)\(1\).\(\newline\)Values of \(f\): \(f\)\(3\), \(f\)\(4\)
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