Răspuns:
Explicație pas cu pas:
5/4*(4/5(2x/3 + 3/2) + 1] - 9/4 = 3
5/4*[4/5(2x/3 + 3/2) + 1] = 3 + 9/4 = 12/4 + 9/4 = 21/4
4/5(2x/3 + 3/2) + 1 = 21/4 : 5/4 = 21/4*4/5 = 21/5
4/5(2x/3 + 3/2) = 21/5 - 1 = 21/5 - 5/5 = 16/5
2x/3 + 3/2 = 16/5 : 4/5 = 16/5*5/4 = 4
2x/3 = 4 - 3/2 = 8/2 - 3/2 = 5/2
x = 5/2 : 2/3 = 5/2*3/2 = 15/4
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Suma unghiurilor = 180°
Unghiul format de bisectoare are 180° : 2 = 90° deci laturile sunt perpendiculare