SOLUTION: if y = 43 +x2 find the value of Y when Y = -2

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Question 1205658: if y = 43 +x2 find the value of Y when Y = -2
Found 4 solutions by MathLover1, ikleyn, josgarithmetic, math_tutor2020:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

y+=+43+%2Bx%5E2+
find the value of Y when Y+=+-2=> I assume you mean x+=+-2
y+=+43+%2B%28-2%29%5E2+
y+=+43+%2B4+
y+=+47+

Answer by ikleyn(52925) About Me  (Show Source):
You can put this solution on YOUR website!
.
if y = 43 +x2 find the value of Y when Y = -2
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        Writing in your post is  FATALLY  INCORRECT,
        making the meaning of your post dark,  unclear and ambiguous.



Answer by josgarithmetic(39631) About Me  (Show Source):
You can put this solution on YOUR website!
Not written correctly.
y=43%2Bx%5E2 ? Is this what you have?


No "Y".
You either mean, "find y" or y=-2 and want to find x.

Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

The question appears to have some typos. Please be more careful when posting the question.

I'll assume the equation is y+=+43%2Bx%5E2 in which you can write as y = 43 + x^2

If you want to find y when x = -2, then...
y+=+43%2Bx%5E2
y+=+43%2B%28-2%29%5E2
y+=+43%2B4
y+=+47


Or if you wanted to find x when y = -2, then...
y+=+43%2Bx%5E2
-2+=+43%2Bx%5E2
-2-43+=+x%5E2
-45+=+x%5E2
x%5E2+=+-45
If your teacher has not covered imaginary numbers just yet, then the answer is "no real solutions" since squaring a real number does not lead to a negative result.


If your teacher has covered imaginary numbers, and requests the complex roots, then the next set of steps are:
x%5E2+=+-45
x+=+sqrt%28-45%29 or x+=+-sqrt%28-45%29
x+=+sqrt%28-1%2A9%2A5%29 or x+=+-sqrt%28-1%2A9%2A5%29
x+=+sqrt%28-1%29%2Asqrt%289%29%2Asqrt%285%29 or x+=+-sqrt%28-1%29%2Asqrt%289%29%2Asqrt%285%29
x+=+i%2A3%2Asqrt%285%29 or x+=+-i%2A3%2Asqrt%285%29
x+=+3i%2Asqrt%285%29 or x+=+-3i%2Asqrt%285%29
That can be condensed to
x+=+%22%22+%2B-+3i%2Asqrt%285%29
where i+=+sqrt%28-1%29