<span>(7y2 + 6xy) – (–2xy + 3)
7y^2 + 6xy +2xy +3
7y^2 +8xy +3
8xy + 7y^2 +3</span>
"2 times pi times r", which can be written as "2*pi*r", represents the circumference of a circle. This is the distance around the circle (aka perimeter)
r is the radius of the circle
if you know the diameter then you can divide the diameter in half to get the radius (example: diameter is 10 so the radius is 5)
Double of 50 is 100, so 28*100=2800, now half of the answer is 2800/2=1400
"A parabola is curved instead of linear, in your case it is probably just facing up or down so I won't get into square roots for now.So the quadratic equation that you probably have had to memorize (or will soon) is:
x=(-b[+or-]√(b²-4ac))/2a when you have an equation like ax²+bx+c=0Now where does the curve shape come from? You see that little pesky plus or minus in the equation? That's because there are always 2 values (inputs) that will generate the same output. Example:y=x²(2)²=4(-2)²=...4So if you were to follow this pattern, and plot the points on a graph, you would end up with a curve. You end up with a curve because the slope is constantly increasing.
And this is actually where you start the study of Calculus(!), which is all about measuring slopes (And a bunch of other stuff, but this is the easiest part to explain). Actually, in this case of y=x², the slope at any given point (funnily enough) is equal to 2 times your x-value.
The point is, your line is curved because unlike a linear equation, the slope is changing (at a constant rate)."
Answer:
OA and OC hope that helps :)