Answer:
R = sqrt[(IWL)^2/(E^2 - I^2)] or R = -sqrt[(IWL)^2/(E^2 - I^2)]
Step-by-step explanation:
Squaring both sides of equation:
I^2 = (ER)^2/(R^2 + (WL)^2)
<=>(ER)^2 = (I^2)*(R^2 + (WL)^2)
<=>(ER)^2 - (IR)^2 = (IWL)^2
<=> R^2(E^2 - I^2) = (IWL)^2
<=> R^2 = (IWL)^2/(E^2 - I^2)
<=> R = sqrt[(IWL)^2/(E^2 - I^2)] or R = -sqrt[(IWL)^2/(E^2 - I^2)]
Hope this helps!
Answer:
y = 2x - 7
Step-by-step explanation:
Looks like we already have the slope of this line: It is 2. Working with the point (1, -5), we have x = 1 and y = -5 and can from this info easily find the y-intercept, b:
y = mx + b becomes
y = 2x + b, which in turn becomes
-5 = 2(1) + b, or
b = -7,
and so the desired equation is y = 2x - 7
Answer:
(x - 10)² + (y + 9)² = 20
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
The radius is the distance from the centre to a point on the circle
To calculate r use the distance formula
r = √(x₂ - x₁ )² + (y₂ - y₁ )²
with (x₁, y₁ ) = (10, - 9) and (x₂, y₂ ) = (12, - 13)
r = 
= 
= 
, hence
(x - 10)² + (y - (- 9))² = ()², that is
(x - 10)² + (y + 9)² = 20
Answer:
80
Step-by-step explanation:
Each boy can be sketched with all of the girls so. 8*10=80
