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2 years ago

Ln triangle PQR, angle P-Q=20 and angle Q-R=50, find the value of angle R

Mathematics

2 answers:

larisa86 [58]2 years ago

7 0

Q: P-Q=20
P-20=Q
R: Q-R=50
Q-50=R
P-20-50=R
P-70=R
P+Q+R=180
P+P-20+P-70=180
3P-90=180
3P=90
P=30

posledela2 years ago

5 0

Answer:

Step-by-step explanation:

The sum of measures of angles in triangle is always 180°:

P + Q + R = 180

Q - R = 50 ⇒ Q = 50 + R

P - Q = 20 ⇒ P = 20 + Q = 20 + 50 + R = 70 + R

so:

P + Q + R = 180

70 + R + 50 + R + R = 180

120 + 3R = 180

3R = 180 - 120

3R = 60

R = 60:3

R = 20

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Ln triangle PQR, angle P-Q=20 and angle Q-R=50, find the value of angle R​

Ln triangle PQR, angle P-Q=20 and angle Q-R=50, find the value of angle R