To find points of intersection, we need to use simultaneous equations.
y = 2x --- 1
y =
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- 3 --- 2
Sub 1 into 2,
2x =
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- 3
0 =
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- 2x - 3
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- 2x - 3 = 0
Factorise,
(x - 3)(x + 1) = 0
Let each bracket equal to 0,
x - 3 = 0 x + 1 = 0
x = 3 x = -1
Sub 3 into equation 1,
y = 2(3)
= 6
Now sub -1 into equation 1,
y = 2(-1)
= -2
Therefore, your two y values are -2 and 6
Hope this helped! Ask me if there's any part of the working you don't understand :)