<PRE><B>Question 79189</B>
Can anyone help me to simplify by combining like terms:
sqrt63 - 2sqrt28 + 5sqrt7 
:
note the squares inside each radical:
{{{sqrt(9*7) - 2*sqrt(4*7) + sqrt(7)}}}
:
Extract those squares:
{{{3*sqrt(7) - 2*2*sqrt(7) + sqrt(7)}}}
:
{{{3*sqrt(7) - 4*sqrt(7) + 1*sqrt(7)}}}
:
Combine like terms and you have:
3 - 4 + 1 = 0 so you have:
{{{0*sqrt(7)}}} or just 0
:
:
you can check it on good calculator: enter:{{{sqrt(63) - 2*sqrt(28) + sqrt(7)}}} It should = 0
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