Answer & Step-by-step explanation:
2a - b : 2a + b = 1 : 2
2a - b = 1
- Elimination
2a + b = 2
-b - (b) = -1
-2b = -1
b = 0.5
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2a + b = 2 Substitution
2a + 0.5 = 2
2a = 1.5
a = 0.75
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a:b
0.75 : 0.5
or
3/4 : 1/2
Hope this helps!!!
Answer:
Step-by-step explanation:19 and 31
The surface area of a sphere is A = 4 π R² .
Sadly, the question doesn't give you 'R', so you have to
back it out of the circumference.
Circumference = π (diameter)
Divide each side by π : Diameter = circumference / π
Radius = 1/2 diameter: Radius = circumference / (2 π)
Area = 4 π R² =
4 π (circumference/2π)² =
4 π (circumference)² / 4 π²
Divide top and bottom by 4π : Area = (Circumference)² / π
Circumference = 37.68 units
Area = (37.68)² square units /π =
<em>451.93 square units</em>
Answer:-1/3
Step-by-step explanation: I really don’t know
Instead of subtracting 6 from 12 then dividing they added 6 to 12 & ended up with 18. 18 by 2 is 9.
