17 because 4 x 1.5 = 6, 50 / 1.5 = 33.33
Same girl oh my god it won’t let me ask anymore questions. Not my fault my math teacher gave me 30 questions to ask
Remark
This is an excellent question. Estimation is a powerful skill to have. People should always shop using estimates. Try it to see what happens.
x = 11.7 which rounds up to which we will call x1 and that is 12
y = 6.03 which round down to 6 which we will call y1 and that is 6
Now x - y = 5.67
If you do the rounded subtraction x1 - y1 = 12 - 6 = 6
The estimate is not zero. D is not correct.
There is enough information E is not the answer.
B is wrong, her estimate is larger than x - y
C is wrong the two subtractions are not equal.
A is correct and always will be no matter what numbers are chosen
A <<<< Answer
Answer:
Step-by-step explanation:
![x^2+y^2-8x+4y+4=0\\\\a)\\\\x^2-8x+y^2+4y+4=0\\\\x^2-2*x*4+(y^2+2*y*2+2^2)=0\\\\x^2-2*x*4+4^2+(y+2)^2=4^2\\\\(x-4)^2+(y+2)^2=4^2\\](https://tex.z-dn.net/?f=x%5E2%2By%5E2-8x%2B4y%2B4%3D0%5C%5C%5C%5Ca%29%5C%5C%5C%5Cx%5E2-8x%2By%5E2%2B4y%2B4%3D0%5C%5C%5C%5Cx%5E2-2%2Ax%2A4%2B%28y%5E2%2B2%2Ay%2A2%2B2%5E2%29%3D0%5C%5C%5C%5Cx%5E2-2%2Ax%2A4%2B4%5E2%2B%28y%2B2%29%5E2%3D4%5E2%5C%5C%5C%5C%28x-4%29%5E2%2B%28y%2B2%29%5E2%3D4%5E2%5C%5C)
Hence,
The radius of the circle is 4 units, coordinates of its centre are (4,-2).
![b)\\\\y=0\\x^2+0^2-8x+4*0+4=0\\x^2-8x+4=0\\a=1\ \ \ \ b=-8\ \ \ \ c=4\\D=(-8)^2-4*1*4\\D=64-14\\D=48\\\sqrt{D}=\sqrt{48} \\ \sqrt{D}=\sqrt{16*3} \\\sqrt{D}=\sqrt{4^2*3} \\\sqrt{D}=4\sqrt{3} \\\displaystyle\\x=\frac{-(-8)б4\sqrt{3} }{2*1} \\\\x=\frac{8б4\sqrt{3} }{2} \\x_1=4-2\sqrt{3} \\x_2=4+2\sqrt{3}](https://tex.z-dn.net/?f=b%29%5C%5C%5C%5Cy%3D0%5C%5Cx%5E2%2B0%5E2-8x%2B4%2A0%2B4%3D0%5C%5Cx%5E2-8x%2B4%3D0%5C%5Ca%3D1%5C%20%5C%20%5C%20%5C%20b%3D-8%5C%20%5C%20%5C%20%5C%20c%3D4%5C%5CD%3D%28-8%29%5E2-4%2A1%2A4%5C%5CD%3D64-14%5C%5CD%3D48%5C%5C%5Csqrt%7BD%7D%3D%5Csqrt%7B48%7D%20%5C%5C%20%5Csqrt%7BD%7D%3D%5Csqrt%7B16%2A3%7D%20%5C%5C%5Csqrt%7BD%7D%3D%5Csqrt%7B4%5E2%2A3%7D%20%20%5C%5C%5Csqrt%7BD%7D%3D4%5Csqrt%7B3%7D%20%20%5C%5C%5Cdisplaystyle%5C%5Cx%3D%5Cfrac%7B-%28-8%29%D0%B14%5Csqrt%7B3%7D%20%7D%7B2%2A1%7D%20%5C%5C%5C%5Cx%3D%5Cfrac%7B8%D0%B14%5Csqrt%7B3%7D%20%7D%7B2%7D%20%5C%5Cx_1%3D4-2%5Csqrt%7B3%7D%20%5C%5Cx_2%3D4%2B2%5Csqrt%7B3%7D)
![c)\\\\A(6,2\sqrt{3}-2)\\ (x-4)^2+(y+2)^2=4^2\\(6-4)^2+(2\sqrt{3} -2+2)^2=16\\2^2+(2\sqrt{3} )^2=16\\4+2^2*(\sqrt{3})^2=16\\ 4+4*3=16\\4+12=16\\16\equiv16](https://tex.z-dn.net/?f=c%29%5C%5C%5C%5CA%286%2C2%5Csqrt%7B3%7D-2%29%5C%5C%20%28x-4%29%5E2%2B%28y%2B2%29%5E2%3D4%5E2%5C%5C%286-4%29%5E2%2B%282%5Csqrt%7B3%7D%20-2%2B2%29%5E2%3D16%5C%5C2%5E2%2B%282%5Csqrt%7B3%7D%20%29%5E2%3D16%5C%5C4%2B2%5E2%2A%28%5Csqrt%7B3%7D%29%5E2%3D16%5C%5C%204%2B4%2A3%3D16%5C%5C4%2B12%3D16%5C%5C16%5Cequiv16)
![d)\\A(6,2\sqrt{3}-2)}\\\sqrt{3} x+3y=\\\sqrt{3}(6)+3(2\sqrt{3} -2)=\\ 6\sqrt{3}+6\sqrt{3} -6=\\ 12\sqrt{3}-6](https://tex.z-dn.net/?f=d%29%5C%5CA%286%2C2%5Csqrt%7B3%7D-2%29%7D%5C%5C%5Csqrt%7B3%7D%20x%2B3y%3D%5C%5C%5Csqrt%7B3%7D%286%29%2B3%282%5Csqrt%7B3%7D%20-2%29%3D%5C%5C%206%5Csqrt%7B3%7D%2B6%5Csqrt%7B3%7D%20-6%3D%5C%5C%2012%5Csqrt%7B3%7D-6)