Answer:
y = (4 -3x)/5
Explanation:
Find the terms containing y. If they are all on one side of the equation (it is), then identify the terms not containing y. Subtract those. Then, divide by the coefficient of y.
3x +5y = 4
5y = 4 - 3x . . . . . non-y term subtracted
y = (4 -3x)/5 . . . . divide by the coefficient of y
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If you like, you can rearrange this to slope-intercept form:
... y = -3/5x +4/5