Solve by completing the square.f2−14f=31Write 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.f2−14f=31Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.f= _____ or f= _____
Write Equation Form: Write the equation in the form of f2+bf=c. The given equation is already in this form: f2−14f=31.
Move Constant Term: Move the constant term to the right side of the equation.Add 31 to both sides to isolate the f2 and f terms on one side.f2−14f+31−31=31+31f2−14f=31
Find Completion Number: Find the number to complete the square.Take half of the coefficient of f, square it, and add it to both sides of the equation.(−14/2)2=49f2−14f+49=31+49f2−14f+49=80
Factor Left Side: Factor the left side of the equation.The left side is now a perfect square trinomial.(f−7)2=80
Take Square Root: Take the square root of both sides of the equation.Remember to consider both the positive and negative square roots.(f−7)2=±80f−7=±80
Solve for f: Solve for f by isolating the variable.Add 7 to both sides of the equation to get f by itself.f−7+7=±80+7f=7±80
Simplify Square Root: Simplify the square root and round to the nearest hundredth if necessary. 80 is approximately 8.94 when rounded to the nearest hundredth. f=7±8.94
Find Values of f: Find the two values of f.f=7+8.94 implies f≈15.94.f=7−8.94 implies f≈−1.94.Values of f: 15.94, −1.94
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