2x − y + 1 = 0
y = 1
−−−−−−−−−−−
to x = 0
A = ( 0; 1)
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x +y − 6 = 0
y = 1
−−−−−
to x = 5
B = ( 5; 1)
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2x − y + 1 = 0 ⇒ y = 2x + 1
x + y − 6 = 0
−−−−−−−−
x + (2x + 1) − 6 = 0
3x − 5 = 0
3x = 5
x = 53
y = 2*53 + 1 = 133 = 413
C = ( 53 ; 133 )
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Pole trójkąta ABC
P = 0,5 *I AB I * h = 0,5 *( 5 − 0) *( 133 − 1) = 2,5 *103 = 253 = 813
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