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Without expanding any brackets, work out the solutions of 9(x+3)^2 = 4

To solve for x first divide both sides by 9, giving the equation:(x+3)² = 4/9Then square root both sides, leading to:x+3 = +/- 2/3Finally subtract 3 from both sides leaving:x = -11/3 or x = -7/...

Answered by Modestas T. • Maths tutor

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Explain why the use of petrol and diesel cars may be a source of market failure.

Pollution from petrol cars is an example of a negative externality (where the actions of one person impact another without the affected person being compensated). In a competitive economy people pay the &...

Answered by • Economics tutor

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Solve the simultaneous equations: 3x + y =11; 2x + y = 8

subtract one from the other to eliminate y: 3x+y=11; 2x+y=8 --> x=3substitute value of x back in and solve for y: 3(3)+y=11; 9+y=11; --> y=2

Answered by Israel H. • Maths tutor

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(a) Expand and simplify (x − 3)(x + 5), ..2 marks.. (b) Solve x^2 + 8x − 9 = 0 ..3 marks..

(a) Remember: Multiply each term in the left bracket by every term in the right bracket.(x-3)(x+5) = x²+ 5x - 3x -15.Collecting all of the like terms:= x²+ 2x -15.
(b) Solve x

Answered by Jack W. • Maths tutor

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What is the difference between simple diffusion and active transport?

Simple diffusion is the movement of a molecules from an area of high concentration to an area of low concentration across a semipermeable membrane. Diffusion happens in liquids and gases as their particle...

Answered by Simi K. • Biology tutor

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