Solve by completing the square.y2−4y=25Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.y= _____ or y= _____
Q. Solve by completing the square.y2−4y=25Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.y= _____ or y= _____
Rewrite in standard form: Write the equation in the form of y2+by=c. The given equation is y2−4y=25.
Move constant term: Move the constant term to the other side of the equation.Subtract 25 from both sides to isolate the y terms.y2−4y−25=0y2−4y=−25
Complete the square:Complete the square by adding the square of half the coefficient of y to both sides.The coefficient of y is −4, so half of that is −2, and the square of −2 is 4.Add 4 to both sides of the equation.y2−4y+4=−25+4y2−4y+4=−21
Factor left side: Factor the left side of the equation.The left side is a perfect square trinomial.(y−2)2=−21
Take square root: Take the square root of both sides of the equation.Remember to include the ± symbol when taking the square root of both sides.(y−2)2=±−21y−2=±−21
No real solutions: Since the square root of a negative number is not a real number, there are no real solutions to this equation.The equation y2−4y=25 does not have real solutions because you cannot take the square root of a negative number in the real number system.
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