Answer :

naǫ
[tex]y=mx+b \\ m=\frac{1}{4} \\ \Downarrow \\ y=\frac{1}{4}x+b \\ \\ (12,9) \\ x=12 \\ y=9 \\ \Downarrow \\ 9=\frac{1}{4} \times 12 + b \\ 9=3+b \\ 9-3=b \\ b=6 \\ \\ \boxed{y=\frac{1}{4}x+6}[/tex]
so first convet to slope intercept form which is y=mx+b where m is slope and b is y intercept

so since you are given x and y values and the slope, you can solve for b

so y=mx+b
y=1/4x+b
subsitute 12 for x and 9 for y
9=1/4(12)+b
9=3+b
6=b


so the equation is y=1/4x+6