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find the values of x when 3x^2 - 6x - 9

First we will need to factorise the equation. Start with the 3x^2 term and notice 3 is prime so must have 3x and x terms. (3x - 9) (x + 1) or (3x + 3) (x - 3) Setting the brackets to 0 gives us 3x - 9 = 0 an...
DM
Answered by Dylan M. • Maths tutor
5451 Views

Solve the simultaneous equations: 4x + 7y = 1, 3x + 10y = 15.

4x + 7y = 1 1. 3x + 10y = 15 2. 1. x 3 (4x x 3) + (7y x 3) = 1 x 3 12x + 21y = 3 3. 2. x 4 (3x x 4) + (10y x 4) = 15 x 4 12x + 40y = 60 4. 4. - 3. (12x - 12x) + (40y - 21y) = 60 - 3 19y = 57 y = 57/19 y = 3 ...
IJ
Answered by Isabelle J. • Maths tutor
6461 Views

Make x the subject of the equation: y = 4(x+2)/5x-1

1st multiply out the brackets: y = 4x + 8 / 5x - 1 Next multiply both sides by the denominator onf the RHS: y(5x-1) = 4x + 8 Again, multiply out the brackets: 5xy - y = 4x + 8 Rearrange the equation so that ...
NR
Answered by Nikilesh R. • Maths tutor
9481 Views

solve the differential equation dy/dx = 6xy^2 given that y = 1 when x = 2

First step is to seperate the variables (EQ1) : (1/y^2) dy = 6x Then we integrate each side seperately giving us (EQ2) : -1/y = 3x^2 + C (remembering to add 1 to the power and divide by the new power) subbin...
DM
Answered by Dylan M. • Maths tutor
10161 Views

How would you determine what sort of stationary point this curve has? x^3 - 6x^2 + 9x - 4

I would differentiate it and then turn it into an equation to find the points where the gradient equals zero. With these points at hand, I would take a second derivative, this tells me how the gradient chang...
WM
Answered by William M. • Maths tutor
6620 Views