Question

Solve the system
-2y+5z=-3
y=-5x-4z-5
x=4z+4

Answer 1

-2y + 5z = -3
y = -5x - 4z - 5
x = 4z + 4

-2(-5(4z + 4) - 4z - 5) + 5z = -3
-2(-20z - 20 - 4z - 5) + 5z = -3
-2(-20z - 4z - 20 - 5) + 5z = -3
-2(-24z - 25) = -3
48z + 50 = -3
- 50 - 50
48z = -53
48 48
z = -1⁵/₄₈
x = 4(-1⁵/₄₈) + 4
x = -4⁵/₁₂ + 4
x = ⁵/₁₂

y = -5(⁵/₁₂) - 4(-1⁵/₄₈) - 5
y = -2¹/₂ + 4⁵/₁₂ - 5
y = 1¹¹/₁₂ - 5
y = -3¹/₂

(x, y, z) = (⁵/₁₂, -3¹/₂, -1⁵/₄₈)