The measurement of ∠B is 168°
Given,
In the question:
Angle A and Angle B are supplementary angles.
If mA (x - 9)° and m/B= (7x + 21)°
To find the measure of ∠B
Now, According to the question;
What are supplementary angles?
Two angles are Supplementary when they add up to 180 degrees.
Now, ∠A+∠B = 180°
So,
⇒(x - 9)˚+(7x + 21)°=180°
=> 8x +12 = 180°
=> 8x = 180° - 12
=> 8x = 168
=> x = 168/8
=> x = 21
For the measure of ∠B :
∠B = (7x + 21)
∠B = 7 x 21 + 21
∠B = 168°
Hence, The measurement of ∠B is 168°
Learn more about Supplementary angles at:
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Answer:
True
Step-by-step explanation:
X+11=18
subtract 11 from both sides
18-11=7
x=7
Answer:
Bro look it up
Step-by-step explanation:
On google
Selection B is appropriate.
_____
The signs of the coefficients tell you the binomial factors must have both signs positive (selections B and C only). Selection B produces an x-term that is 15x+15x=30x (as we want); selection C produces an x-term that is 45x+5x=50x (not what we want).