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Rationalising the denominator (Surds)

When asked to rationalise simple Surd (square roots that cannot be reduced to a whole number) fractions in the form a/√b we are aiming to remove the surd in the denominator (bottom).-------------------------...
GY
Answered by Galen Y. • Maths tutor
20690 Views

Find the inverse of f(x) = 7x+4

To start make the equation equal y. So y = 7x+4 Then rearrange the equation to make x the subject. Subtract 4 from both sides: y-4 = 7x Divide by 7: (y-4)/7 = x Now write it in terms of x f(x)^-1 = (x-4)/7 w...
JS
Answered by Joe S. • Maths tutor
14632 Views

Solve the simultaneous equations: y = 4x^2 - 9x - 1 and y = 5 - 4x

Subtract the second equation from the first, giving you: 4x^2 -5x -6 Factorise the quadratic: (4x + 3)(x - 2) x = -0.75 x= 2 Now substitute these values into one of the equations (or both, just to double-che...
DA
Answered by Damilola A. • Maths tutor
10668 Views

Solve the simultaneous equations: x^2+y^2=36 ; x=2y+6

Substitute x in terms of y into the first equation: (2y+6) 2 +y 2 =36 Use FOIL to expand the brackets 4y 2 +24y+36+y 2 =36 => 5y 2 +24y=0 y(5y+24)=0 => y=0 or y=(-24)/5 Substitute these values of y int...
DB
Answered by Daniel B. • Maths tutor
33787 Views

Can you make 'p' the subject of the following equation? 4(p-2q)= 3p+2

When a question asks you to make something the subject of an equation, it is asking you to rearrange it to get it in the form of, for example when 'p' is the subject, 'p = ....' First we want to expand the b...
SM
Answered by Sarah M. • Maths tutor
20619 Views