Som hoeken is 180 graden
3p
Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(\angle B = 63\degree\) en \(\angle C = 71\degree \text{.}\)
Bereken \(\angle \text{A} \text{.}\)
Rond indien nodig af op één decimaal.
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De som van de hoeken in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\angle B + \angle C + \angle A = 180\degree \text{.}\)
1p
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Dus \(\angle A = 180\degree - \angle B - \angle C \text{.}\)
1p
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\(\angle A = 180\degree - 63\degree - 71\degree = 46\degree \text{.}\)
1p
3p
Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(\angle P = 34\degree\) en \(\angle Q = 33\degree \text{.}\)
Bereken \(\angle \text{R} \text{.}\)
Rond indien nodig af op één decimaal.
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De som van de hoeken in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\angle P + \angle Q + \angle R = 180\degree \text{.}\)
1p
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Dus \(\angle R = 180\degree - \angle P - \angle Q \text{.}\)
1p
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\(\angle R = 180\degree - 34\degree - 33\degree = 113\degree \text{.}\)
1p