Answer:20.096
Step-by-step explanation:
radius =r=4
Φ=288
π=3 14
Length of arc=Φ/360 x 2 x π x r
Length of arc=288/360 x 2 x 3.14 x 4
Length of arc=0.8 x 2 x 3.14 x 4
Length of arc=20.096
Answer:
I'm pretty sure the answer is D.
Step-by-step explanation:
Answer:
l(l - 2) = 168
Step-by-step explanation:
Let w = width
Let l = length
Let A = area
w = l - 2
A = l * w
also, A = 168
equating the two values of A
l * w = 168
l * (l - 2) = 168
l^2 - 2l = 168
l(l - 2) = 168
The explanation for this is one of my favorite pieces of mathematical reasoning. First, let's thing about distance; what's the shortest distance between two points? <em>A straight line</em>. If we just drew a straight line between A and B, though, we'd be missing a crucial element of the original problem: we also need to pass through a point on the line (the "river"). Here's where the mathemagic comes in.
If we take the point B and <em>reflect it over the line</em>, creating the point B' (see picture 1), we can draw a line straight from A to B' that passes through a point on the line. Notice the symmetry here; the distance from the intersection point to B' is<em> the same as its distance to B</em>. So, if we reflect that segment back up, we'll have a path to B, and because it came from of the line segment AB', we know that it's <em>the shortest possible distance that includes a point on the line</em>.
If we apply this same process to our picture, we see that the line segment AB' crosses the line at the point (1, 1)