Question 362199
1.{{{D+E=110}}}
2.{{{E+F=150}}}
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For every triangle,
{{{D+E+F=180}}}
Substitute from eq. 1,
{{{110+F=180}}}
{{{highlight(F=70)}}}degrees
Substitute from eq. 2,
{{{D+150=180}}}
{{{highlight(D=30)}}}degrees
Then from eq. 1,
{{{30+E=110}}}
{{{highlight(E=80)}}}degrees