Escribir la ecuación estándar de un círculo. Dado un círculo en el plano coordenado, Sal encuentra su ecuación estándar, que es una ecuación de la forma (x-a)²+(y-b)²=r².
The area of a circle is A = πr^2. We let A1 And A2 the areas of the circles and r1 and r2 the radius of each, respectivley.
A1 + A2 = 80π
Substitute the formula for the area,
π(r1)^2 + π (r2)^2 = 80π
From the statement, we know that r2=2(r1).
<span>π(r1)^2 + π (2 x r1)^2 = 80π
</span>We can cancel π, we will have
5 x (r1)^2 = 80
Thus,
r1 = 4 and r2 = 8
As y varies directly with x, there is a proportionality constant. As x increases by that certain constant, y also increases. We equate:
y = kx
where k = proportionality constant.
Given the condition, y = 5 when x = 4, then we solve for k:
5 = k(4)
k = 5/4 or 1.25
When y = 8, then
8 = (5/4)(x)
x = 8/(5/4) = (8)(4/5) = 32/5 or 6.4 (ANSWER)
To find the X value of the solution, you would set the two equations equal to each other bu substitution:
if <span>y = -2x + 5 and y = 3x - 2,
</span>-2x + 5 must be equal to 3x - 2
solve for x... you should get 7/5
then, plug that into one of the original equations as X and you would get the Y value, 11/5
This point, (7/5,11/5) is where the two lines cross
Answer: The answer is $15.86
Step-by-step explanation: You would change 6.10 into a fraction, which is 61/10. Then you would mulitply that and that number as a decimal would be 15.86.