Q. Which equation has the same solution as x2−18x−1=−7 ?(x−9)2=75(x+9)2=−87(x+9)2=75(x−9)2=−87
Simplify the Equation: First, let's simplify the given equation x2−18x−1=−7 by adding 7 to both sides to set it equal to zero.x2−18x−1+7=−7+7x2−18x+6=0
Check Option 1: Now, let's look at the first option (x−9)2=75 and expand it to see if it simplifies to the same quadratic equation.(x−9)2=x2−18x+81=75Subtract 75 from both sides to set it equal to zero.x2−18x+81−75=0x2−18x+6=0This matches the simplified version of the given equation.
Check Option 2: Next, let's look at the second option (x+9)2=−87 and see if it can be a valid solution.Since the square of a real number is always non-negative, (x+9)2 cannot equal a negative number like −87. Therefore, this option cannot have the same solution as the given equation.
Check Option 3: Now, let's look at the third option (x+9)2=75 and expand it to see if it simplifies to the same quadratic equation.(x+9)2=x2+18x+81=75Subtract 75 from both sides to set it equal to zero.x2+18x+81−75=0x2+18x+6=0This does not match the simplified version of the given equation.
Check Option 4: Finally, let's look at the fourth option (x−9)2=−87 and see if it can be a valid solution. Similar to the second option, since the square of a real number is always non-negative, (x−9)2 cannot equal a negative number like −87. Therefore, this option cannot have the same solution as the given equation.
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