Solve by completing the square.r2−18r+49=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.r=_____ or r=_____
Q. Solve by completing the square.r2−18r+49=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.r=_____ or r=_____
Write equation in standard form: Write the equation in the form of r2+br=c. The given equation is already in this form: r2−18r+49=0.
Move constant term: Move the constant term to the other side of the equation.Subtract 49 from both sides to isolate the r terms.r2−18r=−49
Complete the square:Complete the square by adding the square of half the coefficient of r to both sides.The coefficient of r is −18, so half of it is −9, and the square of −9 is 81.Add 81 to both sides to complete the square.r2−18r+81=−49+81r2−18r+81=32
Factor left side: Factor the left side of the equation.The left side is a perfect square trinomial and can be factored into (r−9)2.(r−9)2=32
Take square root: Take the square root of both sides of the equation.(r−9)2=±32r−9=±32
Solve for r: Solve for r by isolating the variable.Add 9 to both sides of the equation to isolate r.r=9±32
Simplify and finalize: Simplify the square root and write the final answers.32 can be simplified to 42, which is approximately 5.66 when rounded to the nearest hundredth.r=9±42r≈9+5.66 or r≈9−5.66r≈14.66 or r≈3.34
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