The given equation is: 
To find the line perpendicular to it, we interchange coefficients and switch the signs of one coefficient.
The equation to a line perpendicular to it is:
$ 2y-x=c$
where, $c$ is some constant we have determine using the condition given.
It passes through $(2,-1)$
Put the point in our equation:
$2(-1)-(2)=c$
$c=-2-2$
$c=-4$
The final equation is:
$\boxed{ 2y-x=-4}$
Answer:
And replacing the value of 
we got:
Step-by-step explanation:
For this case we have the long who represent the height 10 cm and the diameter is 6cm. So then the radius is given by:
And the surface area for a cylinder is given by this formula:
And replacing the info given we got:
And replacing the value of we got:
Answer:
55˚
Step-by-step explanation:
1. ∡135˚ = 180-135=45˚
2. p=180-80-45
3. p=55˚
The answer is 128 pi in^3. You have to multiply 4x4, then multiply that by 8 to get 128.
7+8= 15 so the second answer
