i have two algebra questions that my daughter needs to answer

Expand 5(n-1)

and

factorise 5x - 15

could some one please explain to me how to do this .. so i can help her with her homework

thnks

Tania

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- Feb 3rd 2008, 10:57 PMhair pulling mumAlgebra help
i have two algebra questions that my daughter needs to answer

Expand 5(n-1)

and

factorise 5x - 15

could some one please explain to me how to do this .. so i can help her with her homework

thnks

Tania - Feb 4th 2008, 12:04 AMJhevon
when we want to expand brackets, we take each thing just outside the bracket and multiply each thing on the inside. so here we have a 5 on the outside, so we take it and multiply the n on the inside and then the -1 on the inside and just add the answers.

so, $\displaystyle 5(n - 1) = 5*n + 5*(-1) = 5n - 5$

Quote:

factorise 5x - 15

so, $\displaystyle 5x - 15 = 5x - 5(3) = 5(x - 3)$

do you get it?