Answer:
Step-by-step explanation:
To properly apply the substitution method, it will be better for us to rearrange the system of equations to have similar variables on the same side


We can simply evaluate equation 1 to have

y = -20
From the first equation alone, we can evaluate the value of y as -20. This is because only one unknown is present in equation one, hence a single equation is sufficient enough to evaluate it. If to unknowns were present, the two equations would have been utilized to evaluate the solution.
Answer:
c
Step-by-step explanation:
Answer:2.0379775363024693e+21
Step-by-step explanation:
7 + 2x - 6 = -3x - 3 - 4
2x + 1 = -3x - 3 - 4
2x + 1 = -3x - 7
2x + 1 + 3x = -7
5x + 1 = -7
5x = -7 - 1
5x = -8
x = -8/5.