How do you solve y=2x+7; 3x-y=-9 using substitution method. explain

The y's value is given in the first equation.  . Now to solve, we will, plug it's value in the second equation.



Now we have x's value, we will plug it's value in the first equation.(We can plug it in the second one too, but plugging it the first one will make it easier.)

From the figure, it can be seen that the mage A'B'C' is obtained from the pre-image ABC by translating/shifting the vertices of the image by 7 units to the right and 6 units down.

Therefore, the rule represents the translation from the pre-image, ΔABC, to the image, ΔA'B'C' is (x, y) → (x + 7, y – 6).