In y = mx + b form, the slope will be in ur m position and the y intercept will be in the b position.
y = mx + b
slope(m) = -1/2
y int (b) = 1
so ur equation is : y = -1/2x + 1....but we need it in standard form
y = -1/2x + 1....add 1/2 to both sides
1/2x + y = 1....cant have fractions, so multiply everything by 2
x + 2y = 2 <== standard form