Q. Which equation has the same solution as x2−8x−12=7 ?(x−4)2=35(x+4)2=3(x+4)2=35(x−4)2=3
Simplify Equation: Simplify the given equation by moving all terms to one side to set the equation to zero.x2−8x−12−7=0x2−8x−19=0
Check First Choice: Look at the first choice (x−4)2=35 and expand it to see if it matches the simplified equation.(x−4)2=x2−8x+16This does not match the simplified equation x2−8x−19 because the constant term is different (+16 instead of −19).
Check Second Choice: Look at the second choice (x+4)2=3 and expand it to see if it matches the simplified equation.(x+4)2=x2+8x+16This does not match the simplified equation x2−8x−19 because the sign of the x term is different (+8x instead of −8x) and the constant term is different (+16 instead of −19).
Check Third Choice: Look at the third choice (x+4)2=35 and expand it to see if it matches the simplified equation.(x+4)2=x2+8x+16This does not match the simplified equation x2−8x−19 because the sign of the x term is different (+8x instead of −8x) and the constant term is different (+16 instead of −19).
Check Fourth Choice: Look at the fourth choice (x−4)2=3 and expand it to see if it matches the simplified equation.(x−4)2=x2−8x+16This does not match the simplified equation x2−8x−19 because the constant term is different (+16 instead of −19).
Adjust First Choice: Since none of the choices match the simplified equation x2−8x−19 when expanded, we need to check if any of the choices can be transformed to match the simplified equation by moving terms around.Let's add 19 to both sides of the first choice to see if it matches the simplified equation:(x−4)2=35(x−4)2+19=35+19x2−8x+16+19=54x2−8x+35=54This does not match the simplified equation x2−8x−19.
Adjust Second Choice: Add 19 to both sides of the second choice to see if it matches the simplified equation:(x+4)2=3(x+4)2+19=3+19x2+8x+16+19=22x2+8x+35=22This does not match the simplified equation x2−8x−19.
Adjust Third Choice: Add 19 to both sides of the third choice to see if it matches the simplified equation:(x+4)2=35(x+4)2+19=35+19x2+8x+16+19=54x2+8x+35=54This does not match the simplified equation x2−8x−19.
Adjust Fourth Choice: Add 19 to both sides of the fourth choice to see if it matches the simplified equation:(x−4)2=3(x−4)2+19=3+19x2−8x+16+19=22x2−8x+35=22Subtract 22 from both sides to get the simplified equation:x2−8x+35−22=0x2−8x+13=0This does not match the simplified equation x2−8x−19.
Correct Approach: Realize that a mistake was made in the previous steps. The correct approach is to compare the given equation x2−8x−12=7 with the choices by first bringing the equation to the form x2−8x=19 (by adding 12 to both sides and then subtracting 7 from both sides). Then, we should look for a choice that, when simplified, has the form x2−8x=19.
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