Step-by-step explanation:
<h2>
Sum of two complementary angle is 90°</h2><h2 /><h2>
so. </h2><h2>
<R+<S =90°</h2><h2>
12x-3+7x-2=90°</h2><h2>
19x-5=90°</h2><h2>
19x=95°</h2><h2>
X= 5</h2>
<h2>
<R= 60-3=57°</h2>
Check out the picture I've got the full explanations on there
Hope it's clear
4260 is the answer
i dont know what you mean by simplified