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3 years ago

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

1 answer:

6 0

-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)

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(a)

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$\begin{aligned}
\displaystyle \frac{dy}{dx} &= \frac{ dy/ d\theta}{ dx/ d\theta} \\
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