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How do I answer a source question?

Questions that contain sources are usually looking for you to pick out as much information as you can that gives you an idea as to what is going on. They can come in the forms of photographs, paintings, newp...
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Answered by Alice D. • History tutor
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Briefly explain how greenhouses gases trap heat from the sun

The temperature of the earth is a balance between the heat it gets from the sun and the heat it radiates back out into space. Gases in the atmosphere absorb most of the heat that would normally be radiated o...
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Answered by Krish T. • Biology tutor
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A curve is mapped by the equation y = 3x^3 + ax^2 + bx, where a is a constant. The value of dy/dx at x = 2 is double that of dy/dx at x = 1. A turning point occurs when x = -1. Find the values of a and b.

dy / dx = 9x^2 + 2ax + b x = 2, dy / dx = 9(2)^2 + 2a(2) + b = 36 + 4a + b x = 1, dy / dx = 9(1)^2 + 2a(1) + b = 9 + 2a + b 36 + 4a + b = 2(9 + 2a + b) b = 18 x = -1, dy / dx = 0 = 9(-1)^2 + 2a(-1) + 18 9 - ...
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Explain why an ice cube submerged in a drink melts faster than an ice cube on a kitchen surface (the drink, surface and room temperature are all equal). (3 marks)

(1) In the drink, all six faces are in contact with the liquid (or) On the kitchen surface, only one of the faces is in contact with a solid and the rest are in contact with the air (or) On the kitchen surfa...
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Answered by Alistair R. • Physics tutor
2637 Views

Solve the simultaneous equations x^2 + y^2 = 9 and y = 3x + 3

y 2 = (3x + 3) 2 = 9x 2 + 18x + 9 x 2 + 9x 2 + 18x + 9 = 9 10x 2 + 18x = 0 (root a: x = 0) 5x + 9 = 0 (root b: x = -1.8) For x = 0, y = 3(0) + 3 (root a: y = 3) For x = -1.8, y = 3(-1.8) + 3 (root b: y = -2....
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Answered by Alistair R. • Maths tutor
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