SOLUTION: √(x)+√(x-7)=7 I solved this equation in two different ways and I got two different answers but they both work when I check them? (X=28 and x=16)
I did:
√(x)+
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-> SOLUTION: √(x)+√(x-7)=7 I solved this equation in two different ways and I got two different answers but they both work when I check them? (X=28 and x=16)
I did:
√(x)+
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Question 675861: √(x)+√(x-7)=7 I solved this equation in two different ways and I got two different answers but they both work when I check them? (X=28 and x=16)
I did:
√(x)+√(x-7)=7 (then I squared everything)
x+x-7=49
2x=56 x=28
Then I did:
√(x)+√(x-7)=7
√(x-7)=7-√(x) (moved the √(x) to the other side)
x-7=49-14√(x)+x (squared both sides)
-56=-14√(x)
56/14=√(x)
√(x)=4
x=16
You can put this solution on YOUR website! 28 doesn't work
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16 does, however, work
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Here are the looong, somewhat convoluted steps, which should have been taken when you arrived at 28.
Obviously, your second solution was much easier to achive than this...
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-7x + 56x = 784
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49x = 784
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x = 16
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