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Solve algebraically the simultaneous equations: x^2 + y^2 = 25 and y – 3x = 13

(1) x²+ y²= 25 (2) y - 3x = 13 To solve simultaneous equations algebraically we want to rearrange one of the equations to be able to substitute this in to the other equation. In th...

Answered by Maria O. • Maths tutor

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How does the eye respond to light?

The eye responds to bright light to protect the retina from damageThe bright light triggers a reflex that makes the pupils smaller, meaning less light enters the eyeAs with all reflexes, there is a stimul...

Answered by Jonathan A. • Biology tutor

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The equation for the reaction between ammonia and oxygen is shown. 4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2O(g) . Calculate the entropy change of the reaction, using data from the table below.

GAS So / J K^-1 mol^-1 NH3(g) 193 O2(g) 205 NO(g) 211 H2O(g) 189
To calculate the entropy change, use Delta S = sum of products - sum of reacta...

Answered by • Chemistry tutor

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How do I solve simultaneous equations when one is quadratic? For example 3x^2 -2y = 19, 6x-y-14=0

The aim of this question is to find the two solutions which satisfy the quadratic equation. The approach to this can be broken down into a few principle steps: 1) Express y in terms of x. Here 6x-y-14=0 c...

Answered by Angus M. • Maths tutor

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Draw and explain the atomic structure of one atom of Chlorine.

The answer would include a dot-and-cross diagram, displaying at the centre, a nucleus/the chemical symbol for chlorine, followed by three electron shells, the first containing two electrons, the second ei...

Answered by Maya C. • Chemistry tutor

3943 Views