Solve by completing the square.x2−22x−31=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.x= _____ or x= _____
Q. Solve by completing the square.x2−22x−31=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.x= _____ or x= _____
Rewrite equation: Rewrite the equation in the form of x2+bx=c.Add 31 to both sides to set the equation up for completing the square.x2−22x−31+31=0+31x2−22x=31
Add 31: Choose the number to add to both sides to complete the square.Since (−222)2=121, add 121 to both sides.x2−22x+121=31+121x2−22x+121=152
Choose number to add: Factor the left side of the equation.x2−22x+121=152(x−11)2=152
Factor left side: Take the square root of both sides of the equation.(x−11)2=152x−11=±152
Take square root: Solve for x by isolating the variable.To isolate x, add 11 to both sides of the equation.x−11+11=±152+11x=11±152
Solve for x: Calculate the approximate values of x.x≈11±12.33 (since 152 is approximately 12.33)x≈11+12.33 implies x≈23.33.x≈11−12.33 implies x≈−1.33.Values of x: 23.33, −1.33
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