Determine the slope of a linear equation 3x + 2y = 4

Yes it is. It passes the vertical line test :)

To determine the slope, solve for y in order to put the equation of the line in the slope-intercept form: y = mx + b where m is the slope and b is the y- intercept(the value of y when the line passes thru the y-axis.
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3x-2y = -4
3x + 4 = 2y
(3/2)x + 2 = y
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y = (3/2)x + 2 
slope = (3/2) The positve slope tells us the line slopes to the right
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As y varies by 3, x varies in the same direction by 2
the y-intercept is 2 (0,2) a point on the line
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(0, 2) and (2,5) and (-2,-1) are points on the line