Which of the following functions are linear functions and which are positive proportional functions? Y = - 8x y = X-8 y = 5x ^ 2 + 6 y = - 0.5x-1

Which of the following functions are linear functions and which are positive proportional functions? Y = - 8x y = X-8 y = 5x ^ 2 + 6 y = - 0.5x-1

Y = - 8x positive proportional function
Y = X-8 inverse proportion function
Y = 5x ^ 2 + 6 quadratic function
Y = - 0.5x-1 linear function

The following functions are: ① y = 2 + 3 of X; ② y = 3 (3-x); ③ y = 3x-x & # 178; ④ y = - 3 of X; ⑤ y = 5, where is a linear function

This. 2, of course

(3x-y) & # 178; - (2x + y) & # 178; - 5x (X-Y), where x = 3, y = 1

（3x－y）²－（2x＋y）²－5x（x－y）
=9x²-6xy+y²-4x²-4xy-y²-5x²+5xy
=(9x²-4x²-5x²)+(5xy-6xy-4xy)+(y²-y²)
=-5xy
=-5x3x1
=-15

The image of the inverse scale function passes through point a (- 4,3) and intersects with the image of the positive scale function y = - 4x / 3 at point B
Find the coordinates of intersection B

Let the inverse scale function be y = K / X
So the inverse scale function is y = - 12 / X
Substituting y = - 12 / x into y = - 4x / 3
Get - 12 / x = - 4x / 3
4x^2=36
X = plus or minus 3
When x = 3, y = - 4; when x = - 3, y = 4
So the coordinates of point B are (3, - 4) or (- 3,4)