How to solve for x, y, and z in the system of equations? 2x+4y-z=9
-3x+y+z=14
5x+2y+z=-6

If δmtv is reflected across the y-axis, what are the resulting coordinates of point m? a) (-2, 5) b) (-5, 2) c) (5, -2) d) (-2, -5)

Ihave trouble finding the nth term of a linear sequence

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.