Answer:
y = 6x - 43
Step-by-step explanation:
(6, -7) and (8,5)
m=(y2-y1)/(x2-x1)
m=(5 + 7)/(8 - 6)
m= 12/2
m = 6
y - y1 = m(x - x1)
y + 7 = 6(x - 6)
y + 7 = 6x - 36
y = 6x - 43
Step-by-step explanation:
The question is wrong. The correct equation is :

We know that the equation gives the relation between temperature readings in Celsius and Fahrenheit.
Therefore, giving that we know the value in Fahrenheit ''F'' we can find the reading in Celsius ''C''. This define a function C(F) that depends of the variable ''F''.
So for the incise (a) we answer Yes, C is a function of F.
For (b) we need to find the mathematical domain of this function. Giving that we haven't got any mathematical restriction, the mathematical domain of the function are all real numbers.
Dom (C) = ( - ∞ , + ∞)
For (c) we know that the water in liquid state and at normal atmospheric pressure exists between 0 and 100 Celsius.
Therefore the range will be
Rang (C) = (0,100)
Now, we need to find the domain for this range. We do this by equaliting and finding the value for the variable ''F'' :
For C = 0 :
⇒ 
And for C = 100 :
⇒ 
Therefore, the domain as relating temperatures of water in its liquid state is
Dom (C) = (32,212)
For (d) we only need to replace in the equation by
and find the value of C ⇒
⇒

≅ 21.67
C(71) = 21.67 °C
Remark
Many calculators have a key that will do this in one step. Mine is one of them. So let's start with the answer and then we'll do it the long way.
9C3 = 84. You put it into your calculator as 9 2nF nCr 3 =
Solution

3*4*7 = 84 which is what you set out to show.
8.4617....
Hope this helped you :)
Answer:
X - 7 = - 3
X = - 3 + 7
X = 4
the 7 turns positive because it was moved to the other side of the symbol "=" so we reverse the sign
- becomes +
and
+ becomes -