How would you simplify sqrt 7 (3-sqrt 7)+8 sqrt7?

1 Answer
Johnson Z.
Mar 15, 2016

11sqrt(7)-7

Explanation:

1. Distribute the sqrt(7) to each term in the brackets.

color(red)(sqrt(7))(3-sqrt(7))+8sqrt(7)

=color(red)(sqrt(7))*3-sqrt(7color(red)(*7))+8sqrt(7)

=3sqrt(7)-7+8sqrt(7)

2. Since radicals are like variables, you can think of color(blue)(sqrt(7)) in 3color(blue)(sqrt(7)) as a color(blue)("variable"). Thus, add 8sqrt(7) to 3sqrt(7).

=3sqrt(7)+8sqrt(7)-7

=color(green)(|bar(ul(color(white)(a/a)11sqrt(7)-7color(white)(a/a)|)))

Related questions
See all questions in Multiplication and Division of Radicals
Impact of this question
1726 views around the world
You can reuse this answer
Creative Commons License