Q. What is the missing constant term in the perfect square that starts with x2−20x ?
Identify general form: Identify the general form of a perfect square trinomial. A perfect square trinomial is an expression of the form (ax+b)2=a2x2+2abx+b2, where a and b are constants.
Recognize given expression: Recognize that the given expression x2−20x is the beginning of a perfect square trinomial, and it represents the a2x2 and 2abx parts of the general form. Here, a=1 since the coefficient of x2 is 1, and −20 is the result of 2ab.
Calculate value of : Calculate the value of by using the relationship 2ab = −20. Since a = 1, we have 2(1)b = −20, which simplifies to 2b = −20.
Solve for b: Solve for b by dividing both sides of the equation 2b=−20 by 2. This gives us b=−20/2, which simplifies to b=−10.
Find constant term: Find the constant term of the perfect square trinomial by squaring the value of b. Since b=−10, the constant term is b2=(−10)2.
Calculate b2: Calculate the value of b2. We have (−10)2=100.
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