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 ▸

If f(x) = 1/(6x^2), where x not equal to 0, find the rate of change when x=4.


Calculate the rate of change of d(t )=2/(3t), t ≠ 0, when t=6.


Find the gradient of the straight line with equation 4x+3y=12


show y=3x-5 is tangent to x^2 + y^2 +2x -4y - 5 = 0 and the point where they touch