Som hoeken is 180 graden
3p
Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(\angle B = 57\degree\) en \(\angle C = 63\degree \text{.}\)
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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\(\angle A = 180\degree - 57\degree - 63\degree = 60\degree \text{.}\)
1p
3p
Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(\angle L = 38\degree\) en \(\angle M = 39\degree \text{.}\)
Bereken \(\angle \text{K} \text{.}\)
Rond indien nodig af op één decimaal.
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De som van de hoeken in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\angle L + \angle M + \angle K = 180\degree \text{.}\)
1p
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Dus \(\angle K = 180\degree - \angle L - \angle M \text{.}\)
1p
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\(\angle K = 180\degree - 38\degree - 39\degree = 103\degree \text{.}\)
1p