a) Factorise: 2x^2-72, and hence b) find the y-intercept of the line with the equation: y=(2x^2-72)/(4x-24)
a) Take out the common factor, giving: 2(x2-36), idenitfy the difference of two squares and factoise accordingly, giving: 2(x-6)(x+6)
b) you have the facotirse version of the top of the fraction from part a), factorise the bottom, giving: 4(x-6), then cancel and simplify, giving: y=1/2x+3
Then let x=0 to find the y-intercept to be when y=3
IS
Related Maths Scottish Highers answers
All answers ▸Solve algebraically the system of equations: 4x+5y=-3 and 6x-2y=5
Show that the two vectors A= 2i+3j-k and B=3i-j+3k are perpendicular
Find an equation for the straight line AB , giving your answer in the form px+qy=r, where p, q and r are integers. Given that A has co-ordinates (-2,4) and B has co-ordinates (8,-6)
Find the x-coordinates of the stationary points on the graph with equation f(x)= x^3 + 3x^2 - 24x