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A circle with center C has equation x^2 + y^2 + 8x - 12y = 12

Circle equation = (x - a)²+ (y - b)² = r²Where Centre coordinates (a, b) and radius 'r'Therefore x² + y² + 8x - 12y = 12 is to be rewritten in this ...

Answered by Henry K. • Maths tutor

9451 Views

How do I do redox calculations?

For example,Iron(II) sulphate can be oxidised using acidified potassium permanganate solution. Calculate the mass of iron(II) sulphate which will completely react with 200 cm3 of 0.25 mol l-1 acidified pe...

Answered by Collette G. • Chemistry tutor

2782 Views

Rewrite (2+(12)^(1/2))/(2+3^(1/2)) in the form a+b((c)^(1/2))

To solve:Rewrite the top part of the fraction to get it in terms of 3^(1/2)Rationalise the denominatorSimplify
The final answer is 2(3^(1/2)) - 2

Answered by Max M. • Maths tutor

3824 Views

You're on a game show and have a choice of three boxes, in one box is £10, 000 in the other two are nothing. You pick one box, the host then opens one of the other boxes showing it's empty, should you stick or switch?

At the moment of your first choice you have a 1/3 chance of picking the box with the prize and a 2/3 chance of getting nothing. After your choice those probabilities remain locked in and do not change as ...

Answered by Jonathan B. • Maths tutor

8612 Views

You are sitting in a boat on a lake, you have with you in the boat a large rock. You throw the rock out of the boat and it sinks to the bottom of the lake, does the water level of the lake go up, down or stay the same?

Whilst in the boat the rock (and you) are floating, this means that the amount of water displaced by the rock is the mass of the rock. When the rock sinks to the bottom of the lake the amount of water dis...

Answered by Jonathan B. • Physics tutor

10220 Views