ABCD is a parallelogram angle B= 5x+25 and angle D = 8x-5 find x and angle C
Answers
Answer:
Step-by-step explanation:
Given : In a parallelogram ∠A =(2x + 35), ∠C= (3x - 5)
To find : Value of x, m∠A , m∠B , m∠C, m∠D=?
Solution:
Quadrilateral ABCD is A parallelogram.
∴∠A=∠C .........Opposite angles of parallelogram
∴ 2x + 35 = 3x - 5
∴ 35 + 5 = 3x - 2x
∴ 40 = x
∴ x = 40
∴∠A = ∠C = 2x + 35
= 2 x 40 +35
= 80 + 35
∴ ∠A= ∠C = 115°
Adjacent angles of parallelogram are Supplementary
∴ ∠A + ∠B = 180°
∴ 115 + ∠B = 180
∴ ∠B = 180 - 115
∴ ∠B = 65°
∠B = ∠D = 65°.......Opposite angles of parallelogram.
∴ X = 40
∴m∠A = m∠C = 115°
∴m∠B = m∠D = 65°
Answer:
Angle B = Angle D (Opposite Angles of parallelogram)
5x + 25 = 8x – 5
25 + 5 = 8x – 5x
30 = 3x
x = 30/3
x = 10
Angle B = 5x + 25 = 5(10)+25 = 75°
Angle B + Angle C = 180° (Co-Interior Angles)
75° + Angle C = 180°
Angle C = 180° – 75°