Question 302815
It's pretty straightforward. 
Choose an x, plug it into the equation.
{{{x=0}}}, {{{y=-2x+7=-2(0)+7=0+7=7}}}
Now choose two more x's (x=1, x=2) and repeat. 
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Same thing, plug and chug. 
{{{x=0}}},{{{y=x^2-4x=0-0=0}}}
Repeat for {{{x=1}}},{{{2}}},{{{3}}},{{{4}}}