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Factorising help needed

What is
8x^2-30x-27 factorised please?
Thanks

Hello I have moved both of your threads to the maths forum.

We do not provide full solutions in this forum, please post attempts of both of the questions and then we will help you from there. :smile:

Reply 2

anosmianAcrimony

Basically you're looking for a solution in the form (ax+b)(cx+d), where a, b, c, and d are all integers (i.e. they could be negative). Multiplying (ax+b) by (cx+d) should result in your original expression. So think about how a, b, c, and d are related to the coefficients in your expression - that is, how they produce 8, -30, and -27.

Reply 3

doodle_333

it's not so difficult

start with the 27 - the only way to get 27 is to multiple 9 and 3 or 27 and 1(one of which will be negative as it's -27)

so now you know you have (ax +/- 9)(bx +/- 3) or (ax +/- 27)(bx +/- 1)

if you're going to have 8x^2 then axb = 8... so your options are 8x and 1x (8x x 1x = 8x^2) or 2x and 4x (2x x 4x = 8x^2)

so to find out what you use just play around and try the different possibilities (or use some logic)