Question 270294
Let {{{a}}} = the angle in degrees
{{{180 - a}}} = it's supplement
{{{90 - a}}} = it's complement
given:
{{{180 - a = 3*(90 - a)}}}
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{{{180 - a = 270 - 3a}}}
add {{{3a}}} to both sides
{{{180 + 2a = 270}}}
subtract {{{180}}} from both sides
{{{2a = 90}}}
{{{a = 45}}}
The angle is 45 degrees
check:
{{{180 - a = 3*(90 - a)}}}
{{{180 - 45 = 3*(90 - 45)}}}
{{{135 = 3*45}}}
{{{135 = 135}}}
OK