Solve by completing the square.x2−28x−47=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.x2−28x−47=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 47 to both sides to set the equation up for completing the square.x2−28x−47+47=0+47x2−28x=47
Add 47: Choose the number to add to both sides to complete the square.Since (−228)2=196, add 196 to both sides.x2−28x+196=47+196x2−28x+196=243
Choose Number for Completing Square: Factor the left side of the equation.x2−28x+196=243(x−14)2=243
Factor Left Side: Take the square root of both sides of the equation.(x−14)2=243x−14=±243
Take Square Root: Solve for x.To isolate x, add 14 to both sides of the equation.x−14+14=±243+14x=14±243Since 243 is approximately 15.59, we can write:x≈14±15.59
Solve for x: Find the two values of x.x≈14+15.59 implies x≈29.59.x≈14−15.59 implies x≈−1.59.Values of x: 29.59, −1.59
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