Respuesta :

Banabanana
[tex]7 \sqrt{7}-2 \sqrt{28}= 7 \sqrt{7}-4\sqrt{7}= 3 \sqrt{7} [/tex]

A.
gvcci
1. Simplify √28 to 2√7
7√7 - 2×2√7
2. Simplify 2×2√7 to 4√7
7√7-4√7
3. simplify
3√7 is your answer