Direct Variation
y = -1/4x; x = -80
If x = -16 when y = 4, write the direct variation equation and find x when y = 20.
y = -1/3x; y = -2
If x = -18 when y = 6, write the direct variation equation and find y when x = 6.
y = 2x; y = 40
If x = -7 when y = -14, write the direct variation equation and find y when x = 20.
y = 9/10x; x = 10
If x = 10 when y = 9, write the direct variation equation and find x when y = 9.
y = 5/4x; x = 16.8
If x = 12 when y = 15, write the direct variation equation and find x when y = 21.
y = 1/5x; y = 4
If x = 2.5 when y = 0.5, write the direct variation equation and find y when x = 20.
y = 2/9x; x = 202.5
If x = 27 when y = 6, write the direct variation equation and find x when y = 45.
y = 1/6x; x = 252
If x = 36 when y = 6, write the direct variation equation and find x when y = 42.
y = 3x; y = -72
If x = 4 when y = 12, write the direct variation equation and find y when x = -24.
y = 0.5x; y = 2.5
If x = 8 when y = 4, write the direct variation equation and find y when x = 5.
y = -4x; x = -5
If y = -16 when x = 4, write the direct variation equation and find x when y = 20.
y = -3x; y = -18
If y = -18 when x = 6, write the direct variation equation and find y when x = 6.
y = 0.5x; y = 10
If y = -7 when x = -14, write the direct variation equation and find y when x = 20.
y = 10/9x; x = 8.1
If y = 10 when x = 9, write the direct variation equation and find x when y = 9.
y = 4/5x; x = 26.25
If y = 12 when x = 15, write the direct variation equation and find x when y = 21.
y = 5x; y = 100
If y = 2.5 when x = 0.5, write the direct variation equation and find y when x = 20.
y = 4.5x; x = 10
If y = 27 when x = 6, write the direct variation equation and find x when y = 45.
y = 6x; x = 7
If y = 36 when x = 6, write the direct variation equation and find x when y = 42.
y = 1/3x; y = -8
If y = 4 when x = 12, write the direct variation equation and find y when x = -24.
y = 2x; y = 10
If y = 8 when x = 4, write the direct variation equation and find y when x = 5.