The shaded portion area A corresponds to the area Ao of the outer circle minus the area Ai of the inner circle:
A = Ao - Ai
Also, the area of each circle of radius r is given by:
π r²
where the radius r is half the diameter d.
So, using r = d/2 in the above formula, we obtain:
π r² = π (d/2)² = (π/4) d²
Now, replacing each area with the corresponding diameter, we find:
A = Ao - Ai
= (π/4) 4² - (π/4) 1.5²
= (π/4) (4² - 1.5²)
= (π/4) (16 - 2.25)
= (π/4) (13.75)
≅ 10.799
Rounding the result to one decimal place, we find the answer:
10.8 m²
Hope these notes help ! https://mathbitsnotebook.com/Algebra1/Quadratics/QDVertexForm.html
Answer:
See explanation
Step-by-step explanation:
Given a system of equations, you can
- rewrite one of the equations and write the sum of two equations instead of the second equation;
- rewrite one of the equations and write the difference of two equations instead of the second equation;
- rewrite one of the equations and write the sum of the first equation multiplied by one nonzero number and the second equation multiplied by another nonzero number instead of the second equation.
These actions are called elementary row operations. Elementary operations with system of equations do not change the solution set.
Answer:
x = the first mystery number = 2
y = the second mystery number = 0.8
Step-by-step explanation:
Let
x = the first mystery number
y = the second mystery number
8*x + 10*y = 24
8x + 10y = 24
7*x + 10*y = 26
7x + 10y = 26
8x + 10y = 24 (1)
7x + 10y = 26 (2)
Subtract (1) from (2) to eliminate y
8x - 7x = 26 - 24
x = 2
Substitute x = 2 into (1)
8x + 10y = 24 (1)
8(2) + 10y = 24
16 + 10y = 24
10y = 24 - 16
10y = 8
y = 8/10
y = 0.8
x = the first mystery number = 2
y = the second mystery number = 0.8
