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When asked to factor the x^2-100 , a student gives the answer (x-10)(x-10) What is the wrong with this answer?

2 Answers

2 votes
x^2-100
(x-10)(x+10) ...
a^2-b^2 ---> (a-b)(a+b)
User Yung Peso
by
7.8k points
3 votes

Answer:

The student took one factor wrong.

Explanation:

We are given that,

The student factored the polynomial as given below,


x^2-100=(x-10)(x-10)

i.e.
x^2-10^2=(x-10)(x-10)

Since, we know the property,


a^2-b^2=(a+b)(a-b)

So, the correct factorization is,


x^2-10^2=(x+10)(x-10)

Thus, the student took one factor wrong.

User Rbacarin
by
7.8k points