One reason would be if you did not know the answer so you could do
4-5=x
another reason would be if the problem gave you the answer but not one of the things to get the answer
4-x=-1
not sure if that is what you want but I hope this helped
Using a graphing calculator, we can see the graph of the function y = x²-4x+1:
as we can see, the vertex of the function is (2,-3), and the solutions are (0.3,0) and (3.7,0)
Answer: 10 bottles
Step-by-step explanation: 8 x 5 = 40. 2 x 5 = 10
Which means she ran 4160 miles long
if this isn't the answer you wanted, please be more precise
The three points give you three equations, which you can solve by your favorite method.
.. 0m +0n +b = 6
.. 1m +0n +b = -3
.. 0m +2n +b = 5
(m, n, b) = (-9, -1/2, 6)
so the equation of the plane can be written as
.. z = -9x -1/2y +6
_____
In standard form, this would be
.. 18x +y +2z = 12