Question 258447
{{{5sqrt(18) - 4sqrt(98) + 4sqrt(242)}}}
These are not like terms so we cannot add or subtract them as they are. But we can simplify the square roots. Square roots can be simplified if one or more perfect square factors of the radicand (the expression in the radical) can be found. Each of these square roots has a perfect square factor:
{{{5sqrt(9*2) - 4sqrt(49*2) + 4sqrt(121*2)}}}
Now we can use the property of radicals, {{{root(a, p*q) = root(a, p) * root(a, q)}}}, to separate the prefect square factors into their own square roots:
{{{5sqrt(9)*sqrt(2) - 4sqrt(49)*sqrt(2) + 4sqrt(121)*sqrt(2)}}}
Now we can replace the square roots of the perfect squares:
{{{5*3*sqrt(2) - 4*7*sqrt(2) + 4*11*sqrt(2)}}}
which simplifies to:
{{{15*sqrt(2) - 28*sqrt(2) + 44*sqrt(2)}}}
These simplified square roots <i>are</i> like terms so we can now add and subtract them giving:
{{{31sqrt(2)}}}
No further simplifications can be done so this is our answer.