Answer:
y = 5, -4
Step-by-step explanation:
To solve proportions you cross-multiply.
[tex]\frac{2}{y-4} =\frac{y+3}{4} \rightarrow 2\times4 = (y-4)\times(y+3) \rightarrow 8=y^2-y-12[/tex]
Now that we have 8 = y^2 - y - 12, we must make the entire trinomial equal to 0 by subtracting 8 from both sides.
y^2 - y - 20 = 0
Factor the trinomial.
(y - 5)(y + 4) = 0
Make both factors equal to 0 to solve for both values of y.
y = 5, -4