Answer:
<h2>87</h2>
Step-by-step explanation:

Hello,



==> 1+r=5==>r=4
3+3r+3r²+3r^3+...+3r^6=3(1+r+r²+...+r^6)=3*(r^7-1)/(r-1)=4^7-1=16383
The answer is the product of their slope is -1.
First, let's break this down. Perpendicular lines are line with opposite reciprocal slopes. Opposite meaning the inverse sign and reciprocal meaning flipped.
For instance,
If a line had the slope of 5, its inverse would have a slope of -1/5.
Now, if we multiply these numbers together,
5 * -1/5 = -1
The 5's cancel out.
This works for any two perpendicular lines
Answer: I believe its 119 Degrees