Solving systems of equations graphically

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$$y=(x-2)^2+4$$

$$2x+y=7$$

I'm not quite sure how I would graph these. Just a line or parabola? And how would I tell?

Would I expand the first equation or use $2$ and $4$ to get the points?

Any pointers are greatly appreciated.

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1) Draw the parabola (the first equation). Reduce to canonical form, you'll find that the minimum is reached at point $(2,4)$. It crosses $y$-axis at $(0,8)$.

2) Draw line (the second equation). It crosses $y$-axis at $(0,7)$ and $x$-axis at $\left(\frac72,0\right)$.

3) Find their intersection point(s):

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Draw the parabola $y=(x-2)^2+4$ and the line $y=-2x+7$ and find common points.

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prove that $y=-2x+7$ is a Tangent line to the given parabola

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enter image description here

In simple cases the solution can be clearly seen. Like in this plot, the lines have one common point at $(1,5)$, which is also easy to check.