Question 1077501
I can say:
{{{ f(x) = k*x^2 }}}
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When {{{ x=4 }}}, {{{ f(4) = 80 }}}
{{{ 80 = k*4^2 }}}
{{{ 16k = 80 }}}
{{{ k = 5 }}}
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{{{ f(x) = 5x^2 }}}
and
{{{ f(7) = 5*7^2 }}}
{{{ f(7) = 5*49 }}}
{{{ f(7) = 245 }}}