The perimeter is the sum of the side lengths of a shape. <span> A </span>diagonal is a line segment joining two vertices of a polygon or polyhedron <span>when those vertices are not on the same edge. We calculate as follows:
Perimeter = 4a
560 = 4a
a = 140 meters
</span>A=(1/2)d√(4a^2 - d^2)
A = 10240.56 m^2
The new equation after the expression equivalent to x from the first equation is substituted into the second equation is: 
Step-by-step explanation:
We will solve the initial steps for substitution method for finding the correct answer
Given equations are:

From equation one

Putting x = -4y-9 in equation 2

Hence,
The new equation after the expression equivalent to x from the first equation is substituted into the second equation is: 
Keywords: Linear equations, variables
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Answer:
y=(-2/5)x
Step-by-step explanation:
Assuming that the goal is to find the linear equation in slope-intercept form, this problem is pretty simple.
Slope intercept form is y=mx+b, where m is the slope and b is the y-intercept. We just have to plug in the information
y=(-2/5)x+0
Simplifies to:
y=(-2/5)x
Do you have any more information there really is no other way to solve it with out more information