How do I solve this? step by step please 30 POINTS!

The solution to the system of equations is (-7, 5)
Linear equations are equations that have constant average rates of change. Note that the constant average rates of change can also be regarded as the slope or the gradient
A system of linear equations is a collection of at least two linear equations.
In this case, the system of equations is given as
2x + y = -9
3x + 5y = 4
Make y the subject in 2x + y = -9
So, we have
y = -2x - 9
Substitute y = -2x - 9 in 3x + 5y = 4
So, we have
3x + 5(-2x - 9) = 4
Open the bracket
So, we have
3x - 10x - 45 = 4
Evaluate the like terms
-7x = 49
Divide both sides by -7
x = -7
Substitute x = -7 in y = -2x - 9
y = -2(-7) - 9
Evaluate
y = 5
Hence, the solution to the system of equations is (-7, 5)
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