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The point P has coordinates (3, 4) The point Q has coordinates (a, b) A line perpendicular to PQ is given by the equation 3x + 2y = 7 Find an expression for b in terms of a.

y = (7-3x)/2m = ^-3/₂therefore:Y = ²/₃ X + cwhen Y = 4 and X = 3, c = 2therefore b = ²/₃

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How could ionic interactions be used in DNA-RNA hybridisation?

The DNA double helix consists of many hydrogen bonds between the base pairs, but in addition there are negatively charged phosphate molecules as a key component of the sugar-phosphate backbone of DNA stra...

Answered by Mohammed A. • Biology tutor

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A staircase has n steps. You can scale the stairs by taking steps one or two at a time. How many ways are there to scale the steps?

If there are 0 steps, there is 1 possibility (you are already done).If there is 1 step, there is 1 possibility (you take one step).If there are n steps, your first choice is either 1 step or 2 steps:Choic...

Answered by • Oxbridge Preparation tutor

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A staircase has n steps. You can scale the stairs by taking steps one or two at a time. How many ways are there to scale the steps?

If there are 0 steps, there is 1 possibility (you are already done).If there is 1 step, there is 1 possibility (you take one step).
If there are n steps, your first choice is either 1 step or 2 steps...

Answered by • Oxbridge Preparation tutor

2037 Views

A pen is the shape of an equilateral triangle. A goat is attached to a corner of the pen on a rope. The goat eats all the grass it can reach. It can just reach the opposite fence of the pen. What percentage of the grass in the pen does the goat eat?

Step 1: Area of the penA triangle’s area is base * height / 2. Let one side (the base) have length x. By splitting the triangle in half and using Pythagoras’s rule, we get x² = (x/2)^...

Answered by Max C. • Maths tutor

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