Factorise 6x^2 + 7x + 2

6x^2 + 7x + 2 can be written in the form ax^2 + bx + c. In order to factorise this I use the following method which can be used to factorise similar equations. Multiply 'a' and 'c' to get ac (here this is 6 x 2 = 12). Next, you have to look for factors of ac (12) which sum to get the coefficient for b. So here we have 3 and 4 (factors of 12) which add to 7. You can then write the equation in the following form: 6x^2 + 7x + 2 = (6x + 3)(6x + 4)/6,  Similarly, for any equation this would be ax^2 + bx + c = (ax + m)(ax + n)/a, where m and n are the coefficients which you found earlier. Using this, you simplify the right hand side by canceling down to remove the action of dividing by 6. (6x + 3)(6x + 4)/6 => (2x + 1)(6x + 4)/2 => (2x + 1)(3x + 2) which is the complete factorisation of 6x^2 + 7x + 2. 

HP

Related Further Mathematics GCSE answers

All answers ▸

The equation 3x^2 – 5x + 4 = 0 has roots P and Q, find a quadratic equation with the roots (P + 1/2Q) and (Q + 1/2P)


Find and describe the stationary points of the curve y = x^2 + 2x - 8


Find the coordinates of any stationary points of the curve y(x)=x^3-3x^2+3x+2


y=(6x^9 +x^8)/(2x^4), work out the value of d^2y/dx^2 when x=0.5