Step-by-step explanation:
Option 1:
−3x + y = 4.........eq. 1
−9x + 5y = −1.....eq. 2
from eq. 1,
we get y = 4 +3x...................eq. 3
substitute eq. 3 into eq. 2.
-9x + 5(4 +3x) = -1
-9x + 20 + 15x = -1
-9x + 15x = -1 – 20
6x = -21
x = –3.5
to solve y, use the obtained x in eq. 3,
y = 4 + 3(–3.5)
y = -6.5
