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1 vote
Also,How do I factorise these?

x²-49

x²-9

x²-16​

User Cryptonkid
by
4.3k points

2 Answers

4 votes

Answer:

Use the formula (x-a)(x+a)=x^2 - a^2

so what is the square root of 49, 9, and 16? By finding the square root you get a, and you can just plug it into the formula. For example the first one, 7 is the square root of 49. So, (x-7)(x+7)

User C Black
by
4.6k points
4 votes

Answer:

Explanation:

x2 - 49

Both are squares so

Square root (x2) - Square root (49)

= x - 7

The other two answers are x - 3 and x - 4

User Kjetil Joergensen
by
4.0k points