Yes, stop signs are octagon shaped. So, true.
<span>Multiply one of the equations so that both equations share a common complementary coefficient.
In order to solve using the elimination method, you need to have a matching coefficient that will cancel out a variable when you add the equations together. For the 2 equations given, you have a huge number of choices. I'll just mention a few of them.
You can multiply the 1st equation by -2/5 to allow cancelling the a term.
You can multiply the 1st equation by 5/3 to allow cancelling the b term.
You can multiply the 2nd equation by -2.5 to allow cancelling the a term.
You can multiply the 2nd equation by 3/5 to allow cancelling the b term.
You can even multiply both equations.
For instance, multiply the 1st equation by 5 and the second by 3. And in fact, let's do that.
5a + 3b = –9
2a – 5b = –16
5*(5a + 3b = -9) = 25a + 15b = -45
3*(2a - 5b = -16) = 6a - 15b = -48
Then add the equations
25a + 15b = -45
6a - 15b = -48
=
31a = -93
a = -3
And then plug in the discovered value of a into one of the original equations and solve for b.</span>
Answer:

Step-by-step explanation:

Distribute the parenthesis

Add 20 to both sides

Divide both sides by 2


Hope this helps
As given by the question
There are given that the point of two-line

Now,
From the condition of a parallel and perpendicular line
If the slopes are equal then the lines are parallel
If the slopes are negative reciprocal then the lines are perpendicular
If the slopes are neither of the above are true then lines are neither
Then,
First, find the slope of both of line
So,
For first-line, from the formula of slope

Now,
For second-line,

The given result of the slope is negative reciprocal because

Hence, the slope of line1 is -1/2, and slope of line2 is 2 and the lines are perpendicular.