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y is inversely proportional to x. y = 0.04 when x = 80. Find the value of y when x = 32.

If y is inversely proportional to x. We know that y=k/x for some constant k. We need to find this constant before continuing. Looking at the information given to us in the question we know for one example...

Answered by Tyler T. • Maths tutor

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solve the simultaneous equations 8x + 2y = 48 , 14x + 6y = 94

Step 1) Rearrange the first equation to make y the subject: 8x + 2y = 48 , 2y = 48 - 8x , y = 24 - 4x. step 2) Sub y = 23 - 4x into the second equation: 14x + 6(24 -4x) = 94 , 14x + 144 - 24x = 94 Step 3)...

Answered by Harrison S. • Maths tutor

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CO(g) + 2H2(g) ⇌ CH3OH(g). A pressure of 100 atmospheres is used instead of atmospheric pressure. The higher pressure gives a greater yield of methanol and an increased rate of reaction. Explain why.

4 marksExplanation: Increasing the pressure (gases) of reactions increases the frequency of collisions, therefore increasing the rate of reaction.If the ...

Answered by George O. • Chemistry tutor

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l1 and l2 are tangents of a circle. l1 intersects the circle at (3-√3,5) with a gradient of √3, and l2 intersects the circle at (3+√2,4+√2) with a gradient of -1. Find the centre of the circle, and hence find the radius of the circle.

To first find the centre of the circle, the key fact to remember is that the radius of a circle is normal (perpendicular) to any tangent. This means if you take the normals to both of these tangents at th...

Answered by James B. • Further Mathematics tutor

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What are the six modal verbs in German?

The six modal verbs are müssen (to have to), können (to be able to), wollen (to want (to)), sollen (to be supposed to), dürfen (to be allowed to), and mögen (to like).They behave differently to other verb...

Answered by Holly R. • German tutor

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