D=(x2+x1)+(y2-y1) this is the formula I need number 19 Please will mark brainliest and 50 points
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Answer:
[tex]2\sqrt{2}[/tex] or [tex]\sqrt{8}\\[/tex]
Step-by-step explanation:
The formula is actually d= [tex]\sqrt{(x_{2}-x_{1})^{2} + (y_{2}-y_{1})^{2}}[/tex]. Now first, we have to find points A and C.
Point A is (1,2) and Point C is (-1,0).
Now we have to substitute the values in. That would make it d =[tex]\sqrt{(-1-1)^{2} + (0-2)^{2}}[/tex].
To simplify the parentheses, it would get to d= [tex]\sqrt{(-2)^{2}+(-2)^{2} }[/tex].
To simplify the exponents, it would get to d = [tex]\sqrt{4+4}[/tex].
To simplify the square root, it would get to d = [tex]\sqrt{8}[/tex].
So the answer is either [tex]2\sqrt{2}[/tex] or [tex]\sqrt{8}\\[/tex].
Hope this helped! If not, please let me know!