No, they forgot to switch variable labels after solving for the independent variable...
y=-8x+4
y-4=-8x
(y-4)/-8=x
Now that you have solved for the independent variable x, you switch the variable labels...
y=(x-4)/-8
f^-1(x)=(x-4)/-8 which should really be rewritten as:
f^-1(x)=(4-x)/8 :P
I'm gonna send you a picture because it'll explain the answer better
Answer:
46.2
Step-by-step explanation:
If you divide 231 by 5 then you get that answer.
This is a parabola which opens upwards and the directrix will be of the form
y = k
the general form is
4p(y - k) = (x - h)^2 we have:-
1/4(y + 3) = (x - 2)^2
so the vertex is at (2, -3)
4p = 1/4 so p = 1/16
so the focus will be at (2 , -2 15/16)
and directrix is y = -3 1/16
Answer:
x + 3 + 45° = 180°. isosceles triangle
x = 180° - 45°-3°
x = 132°
90° + x = 180°
x =180° - 90°
x = 90°