Answer:
56
Step-by-step 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
[tex]180=3x+5+8x-12\\[/tex]
step 1 combine like terms
[tex]3x+8x=11x\\5-12=-7[/tex]
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
