Explanation?: Rewrite the equation for the line in slope-intercept form: y=3x-4 The slope of this line is m = 3. A line perpendicular to this line passing through point A(-2,3) has a slope m= -1/3. The y-intercept for this perpendicular line [go down 2/3 and over 2 from A(-2,3) which is calculated from the slope to get to x-0] is (-2,3) + (2,-2/3) = (0,2 1/3), so b = 2 1/3. The equation for this perpendicular line is y=(-1/3)x+2 1/3 or x+3y=7 Solving the system of two linear equations with two unknows substituting y=3x-4 into this equation:: x+3(3x-4)=7 Solve for x: 10x-12=7 x=19/10 19/10 + 3y = 7 30y=70-19 y = 51/30 check: 51/30 =? 3(19/10) - 4 51/30=?57/10-40/10 17/10=17/10
