Let $R_A$ be the reaction force at A and $R_E$ be the reaction force at E. The sum of vertical forces must be zero:
$R_A + R_E - 700 - 300 - 400 = 0$
$R_A + R_E = 1400$ (1)
The sum of moments about point A must be zero:
$R_E \times (6 + 4 + 4 + 6) - 700 \times 6
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