1 and 2 are right because one has adjacent. 2 vertical angles. Vertical angles mean the same plane and adjacent means two sides of an X.
The ordered pair that is the best estimate for the solution of the system of equations is (7, 1/2)
The given system of equations is:

Equate equations (1) and (2)

Solve for x in the equation above

Substitute x = 7 into equation (1)

The ordered pair that is the best estimate for the solution of the system of equations is (7, 1/2)
Learn more on system of equations here: brainly.com/question/13729904
The solutions to the given system of equations are x = 6 and y = -5
<h3>Simultaneous linear equations</h3>
From the question, we are to solve the given system of equations
The given system of equation is
4x+5y=-1
-5x-8y=10
Multiply the <u>first equation</u> by 5 and the <u>second equation</u> by 4
5× (4x+5y=-1)
4× (-5x-8y=10)
20x + 25y = -5
-20x - 32y = 40
------------------------
0x + (-7y) = 35
-7y = 35
y = 35/-7
y = -5
Substitute the value of y into the first equation to find x
4x + 5y = -1
4x + 5(-5) = -1
4x -25 = -1
4x = -1 +25
4x = 24
x = 24/4
x = 6
Hence, the solutions to the given system of equations are x = 6 and y = -5
Learn more on Simultaneous linear equation here: brainly.com/question/12647791
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