Can anybody tell me how to solve this;
If xy + z = x(y + z), which of the following must be true?
a) x = 0 and z = 0
b) x = 1 and y = 1
c) y = 1 and z = 0
d) x = 1 and y =0
e) x = 1 and z = 0
The answer is E, I solved for x and got one, however, I'm uncertain on how the answer is z = 0 and not y = 0
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Algebra question
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ornelaspedro
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keizer Soze
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The last equation is z=zx
so here x=1 and z must be 0
y could be 0 also, but it musn´t be 0, it could be any other number. I think that there is the key.
so here x=1 and z must be 0
y could be 0 also, but it musn´t be 0, it could be any other number. I think that there is the key.
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marcusking
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So what I don't get is why c wouldn't be a possibility too.ornelaspedro wrote:Can anybody tell me how to solve this;
If xy + z = x(y + z), which of the following must be true?
a) x = 0 and z = 0
b) x = 1 and y = 1
c) y = 1 and z = 0
d) x = 1 and y =0
e) x = 1 and z = 0
The answer is E, I solved for x and got one, however, I'm uncertain on how the answer is z = 0 and not y = 0
x=-5
y=1
z=0
-5*1 + 0 = -5(1+0)
With c both sides would always be equal to the value of x
I understand E works but doesn't C also?
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keizer Soze
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C is a posibility, but there Y could be any other number, and the question asked which MUST be true... you can´t be sure that y=1... it could be y=2 or y=3...
