s |y+x|= 9 a function? why or why not? I'm not sure I was guessing it wasnt due to the absolute but I am unsure .thank
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It's not a function, and you're right, it's because of the absolute value.
A function must have a unique y-value for every x-value. That's why sqrt(x) is a function and x^(1/2) is not.
Imagine that x = -10. Then if y = 1, |y + x| = |-9| = 9
However, if y = 19, then |y + x| = |9| = 9
So since (-10,1) and (-10,19) are both points on this curve, it's not a function.
A function must have a unique y-value for every x-value. That's why sqrt(x) is a function and x^(1/2) is not.
Imagine that x = -10. Then if y = 1, |y + x| = |-9| = 9
However, if y = 19, then |y + x| = |9| = 9
So since (-10,1) and (-10,19) are both points on this curve, it's not a function.