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PLS HELP :) Factorise fully the following:

a) x² + x
b) 3x - 9x
c) 7x - 35x
d) 4x^3+ 24x
^2

PLS HELP :) Factorise fully the following: a) x² + x b) 3x - 9x c) 7x - 35x d) 4x-example-1

1 Answer

3 votes

Answer:

a) x(x+1)

b) 3x(1-3)

c) 7x(1-5)

d) 4x²(x+6)

Explanation:

When factorising, the most important thing to do is find what the terms have in common. Divide each term by what they have in common, then multiply it by the entire expression so the value doesn't change. Also, you can always check your answer by multiplying it out to see if you get what you started with.

a)

x² + x, both terms have 'x' in common:

x( (x²/x) + (x/x) ) = x(x+1)

b)

3x - 9x, both terms have '3x' in common:

3x( (3x/3x) - (9x/3x) ) = 3x(1-3)

c)

7x - 35x, both terms have '7x' in common:

7x( (7x/7x) - (35x/7x) ) = 7x(1-5)

d)

4x³+ 24x², both terms have 4x² in common:

4x²( (4x³/4x²) + (24x²/4x²) ) = 4x²(x+6)

User Michal Ostruszka
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