Answer:
56
Explanation:
Hey There!
so this is a parallelogram so opposite angles are congruent
So basically what i am saying is that angle P is congruent to angle R
So we need to solve for x
We know that angle P and angle Q are supplements meaning that they will add up to 180
so we setup the equation
![180=3x+5+8x-12\\](https://img.qammunity.org/2022/formulas/mathematics/college/r3mkvbb96gpaak0rk8ibktxem4q7pgd9mk.png)
step 1 combine like terms
![3x+8x=11x\\5-12=-7](https://img.qammunity.org/2022/formulas/mathematics/college/8zfseqp8j229oywb45gu0pfsnuy4r8sdog.png)
now we have
180=11x-7
step 2 add 7 to each side
180+7=187
-7+7 cancels out
now we have
187=11x
step 2 divide each side by 11
187/11=17
x=17
now we plug in 17 to (3x+5) to get the value of angle R
17x3=51
51+5=56
therefore m∠R = 56