Question -
Answer -
(i) ∠A = 70°, ∠B = 72°, ∠C = Z
Δ के तीनों अन्तः कोणों का योग 180° होता है।
∠A + ∠B + ∠C = 180
70 + 72 + Z = 180
142 + Z = 180
Z = 180 – 142
Z = 38
अतः ∠Z = 38°
(ii) ΔACD में
∠A = 50°, ∠C = y, ∠D = 80°
∠A + ∠C + ∠D = 180°
50 + y + 80 = 180
130 + y = 180
y = 180 – 130
y = 50
तथा ΔABC में,
∠A = 40°, ∠B = x°, ∠C = 45°
∠A + ∠B + ∠C = 180°
40 + x° + 45 = 180
85 + x = 180
x = 180 – 85
x = 95
(iii) ΔBCD में,
∠CBD = 55°, ∠BDC = 60°, ∠BCD = x
∠CBD + ∠BCD + ∠BDC = 180°
55 + x + 60 = 180
115 + x = 180
x = 180 – 115
x = 65