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Solve the simultaneous equations algebraically.

x^2 + y^2 = 29y - x = 3Rearrange the second equation such that one variable, either x or y, is the subject. I will rearrange to make x the subject. x = y - 3. Substitute the new equation into equation 1 in p...
JA
Answered by Jane A. • Maths tutor
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Prove that (3n+1)²-(3n-1)² is a multiple of 4 taking into account that n is a positive integer value

Square the brackets (3n+1)²= (3n+1)(3n+1) = 9n²+3n+3n+1 = 9n²+6n+1 (3n-1)²= (3n-1)(3n-1) = 9n²-3n-3n+1 = 9n²-6n+12. Write out the full equation (9n²+6n+1) - (9n²-6n+1) = 9n²+6n+1-9n²+6n-1 = 12n3. Explain you...
NK
Answered by Nalin K. • Maths tutor
7609 Views

How do you solve two simultaneous equations? (i.e. 5x + y =21 and x - 3y =9)

There are two ways of solving the simultaneous equations. The easiest one is to write two equations beneath each other and then try to get either x or y values the same on both of them by multiplying the val...
PM
Answered by Paulina M. • Maths tutor
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Explain the process of how giraffes may have evolved to have long necks (6 marks)

There is natural variation in the lengths of giraffes' necks. As there will be competition for food with other giraffes and other species, those with longer necks would reach leaves on the trees which others...
KS
Answered by Kate S. • Biology tutor
10500 Views

How does a vaccination protect an individual from illness and how is the spread of a pathogen reduced by immunising a large proportion of the population?

In a vaccination there are small quantities of a dead or inactive version of the pathogen .When you inject it into the individual's body an immune response is stimulated against the ' foreign body '. The whi...
CD
Answered by Ciara D. • Biology tutor
4513 Views