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Given that the image of positive scale function y = KX passes through (2,3a) and (a, - 6) (a is greater than 0), the value of X when y = 3 is obtained
∵ image points (2,3a) and (a, - 6)
∴
{2k=-3a①
{ak=-6②
From ①, k = - 3 / 2a, ③
Substitute (3) for (2)
-3/2a^2=-6
a^2=4
∵a＞0
∴a=2
Substituting a = 2 into (1) leads to
k=-3
∴y=-3x
When y = 3
-3x=3
x=-1
Have a good time
The image of a positive scale function is known to pass through points (3,2). (1) find the analytic expression of the function. (2) draw the image of the function. (3) if the point P (3m, 6) is on this line, find the value of M
Let the analytic formula be y = KX
Bring (3,2) into: 2 = 3k, k = 2 / 3
So the relation is y = 2 / 3x
2) The straight line drawn through (0,0) (1,2 / 30) is
3) Bring (3m, 6) into:
6=2/3*3m
m=3
Let the image of a positive scale function pass through point a (negative 2,3) and write the expression of the function. Let the analytic expression of the positive scale function be y = KX
Substituting the point (- 2,3) into the analytic expression, we get 3 = - 2K, and the solution is k = - (3 / 2)
So the analytic expression of the function is y = - (3 / 2) X
Yes
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