Step-by-step explanation:
The upstream speed is S / t₁, and the downstream speed is S / t₂.
If we say f is the speed of the fish in calm water, and r is the speed of the river, then:
f − r = S / t₁
f + r = S / t₂
If we say T is the time it takes to cross the river, then the speed perpendicular to the river is ℓ/T, the speed parallel to the river is r, and the overall speed is f.
Using Pythagorean theorem:
f² = (ℓ/T)² + r²
f² − r² = (ℓ/T)²
(f − r) (f + r) = (ℓ/T)²
(S / t₁) (S / t₂) = (ℓ/T)²
S² / (t₁ t₂) = (ℓ/T)²
(t₁ t₂) / S² = (T/ℓ)²
√(t₁ t₂) / S = T/ℓ
T = ℓ√(t₁ t₂) / S
Answer:
- m = (2-(-2))/(2-(-2)) = 4/4 = 1
- y +2 = 1(x +2)
Step-by-step explanation:
The point-slope form of the equation for a line with slope m through point (x1, y1) is ...
y -y1 = m(x -x1)
To find the slope of the line, find the ratio of the difference in y-values of the points to the difference in corresponding x-values. Here, the slope is ...
m = (2 -(-2))/(2 -(-2)) = 4/4 = 1 . . . work to compute slope
The problem statement tells you x1 = -2, y1 = -2. Putting the numbers in to the point-slope form gives ...
y -(-2) = 1(x -(-2))
y + 2 = x + 2 . . . equation form with m, (x1, y1) filled in
__
The answer at the top leaves the slope shown as 1. We don't know how much simplification you are expected to do. Obviously, this <em>could</em> be simplified to y=x, but then the use of (-2, -2) for the point would not be obvious.
1.330
2.930
3.30
4.80
5.90
6.140
7.10
8.110
Answer: 90º
Step-by-step explanation: complimentary angles are either of the two angles whose sum is 90º