The product of half my number times my number is 162.What is twice my number? Explain how you solved that problem.

Question

I am really confused on a step and I want to make sure it's right because I want a 100 on my math test!

Answer 1

Let the number be x. Half the number is x/2 so the product required is x^2/2=162, and x=√324=18. Therefore twice the number is 36. (Half the number is 9 multiplied by the number is 9*18=162.) Note that x can also be -18 so twice this is -36. There are two solutions for twice the number: 36 and -36.