Question 947839
Small Triangle:
{{{(1/2)*4*h=10}}} using h as the height.
{{{highlight_green(h=5)}}}.


Big Triangle:
This is similar to the small triangle, given.
Proportion according to {{{height/base}}},
a is the height of this big triangle,
{{{a/12=5/4}}}


{{{a=(12)(5/4)}}}


{{{highlight(a=15)}}}