keeping in mind that a year has 12 months, thus 6 months is really 6/12 of a year.
There is one solution:
use elimination method
5x - 7y = 12
5y - 2x = -7 ---> change equation around
5x - 7y = 12
-2x + 5y = -7
2 x ( 5x - 7y) = 2 x (12) multiply both sides by 2
5 x (-2x +5y) = 5 x (-7)
this give you
10x - 14y =24
-10x+25y = -35 add down
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11y = - 11 x is eliminated to find y value
y = -1 input to one of the original equations
5(-1) - 2x = -7
-5 - 2x = -7
+5 +5 add 5 to both sides
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-2x = -2
x = 1
your coordinates for when they intersect is at (1, -1)
one solution
Plug in -1 for x and work it ou'
g(-1) = (-1)^3 + 6(-1)^2 + 12(-1) + 8
= -1 + 6 - 12 + 8
= 1
Answer: Alternate Interior Angles Theorem
