Answer:-12
Step-by-step explanation:
Answer:
Refraction is what happens when light passes through some medium and changes it's direction because of it. For instance, when light travels through a lens light is bent as it goes from air to glass and back to air again. :)
Answer:
9
Step-by-step explanation:
Compare your x2 + y2=81 to the following:
x^2 + y^2 = 81
The " ^ " symbol indicates exponentiation.
Now compare x^2 + y^2 = 81 to
x^2 + y^2 = r^2.
This is the standard equation of a circle of radius r centered at the origin, (0,0). You can see for yourself that 81 must equal r^2.
Taking the square root of 81, we get plus or minus 9.
But the radius must be positive, so we reject the -9 and take +9.
The radius is 9.
I don't see anything, but any line that doensnt have the right angle sign is not perpendicular.
It would be less because when you multiply something by 1/2 you are basically dividing it by 2, finding half. So when you multiply 9 8/9 by 1/2 your product would be less than 9 8/9
