Find the value of the parameter x.
x2−25=0
We will factor using the shortened multiplication formulas:
a2−b2=(a−b)(a+b)(a−b)2=a2−2ab+b2
(a+b)2=a2+2ab+b2
Remember that there might be more than one solution for the value of x.
According to the first formula:
x2=a2
We'll take the square root:
x=a
25=b2
We'll take the square root:
b=5
We'll use the first shortened multiplication formula:
a2−b2=(a−b)(a+b)
x2−25=(x−5)(x+5)=0
Therefore:
x+5=0
x=−5
Or:
x−5=0
x=5
x=5,x=−5