Question

Factor completely. 81-100x^2

Answer 1

Answer:

(9-10x)(9+10x) (I think this is the answer but I'm not one hundred percent sure)

Step-by-step explanation:

First, you can recognize that both numbers (-100x^2 and 81) are a difference of squares, in which means that they both can be square routed. Then, plug in the square routes of the numbers into (9-10x)(9+10x). 9 is the square route of 81 and 10 is the square route of 100. Make sure that when you put the numbers in the parenthesis that there is one negative and positive number since a negative multiplied by a positive makes a negative, hence making 100 negative. I hope that helped.

Answer 2

Answer:

(9 + 10x)(9 - 10x)

Step-by-step explanation:

81-100x²

recall that 81 = 9² and 100 = 10²

hence,

81  -  100x²

= 9²  - 10²x²

= 9² - (10x)²

recall the algebraic property:

a² - b² = (a+b)(a-b)

applying this to our question,

9² - (10x)²

= (9 + 10x)(9 - 10x)