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Solve these simultaneous equations: 2x + y = 7, and 3x - y = 8. Do so by 1) Eliminating an Unknown and 2) Substitution.

The number 'in front of' an unknown is called the Coefficient. When eliminating an unknown, look to see whether the coefficients of x are the same in both equations, or if the coefficients of y are the same....
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Answered by Ellie H. • Maths tutor
3927 Views

Why protons held together in the nucleus?

Alike atoms, protons are also made of smaller particles - mesons. When protons are at very close distance mesons are bonded together by the Strong Nuclear Force, which is stronger than the Electric Force, bu...
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Answered by Eugeniu D. • Physics tutor
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What is the difference between plastic and elastic collision?

An elastic collision is a collision where objects will bounce after they hit each other. For example balls in a pool game bounce after heating each other. For an elastic collision, Mechanical Energy Kinetic ...
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Answered by Eugeniu D. • Physics tutor
30214 Views

How do I know when to use le passé simple or l'imparfait ?

In French, both le passé simple and l'imparfait are used for past situations. However, they are not used the same way. Le passé simple is used for short, sudden actions such as : "Out of the blue, she s...
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Answered by Lou A. • French tutor
2958 Views

A source of green laser light has a wavelength of 560nm, what is its frequency? Give your answer to an appropriate number of significant figures and using the correct units.

1.) using the wave speed formula for an electromagnetic wave, c=fλ, (c=3.00x10^8 m/s) f=c/λ where c=the speed of an electromagnetic wave. f=(3.00x10^8)/(560x10^-9)= 5.36x10^14 Hz
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Answered by Joel E. • Physics tutor
3560 Views