Science:Math Exam Resources/Courses/MATH152/April 2015/Question B 1 (a)

MATH152 April 2015
Other MATH152 Exams

Question B 1 (a)

Uno, Duo and Traea are three friends. They all owe money to a loan shark. All together they owe $600. Duo owes$200 more than Uno. Uno and Duo combined owe as much as Traea.

(a) Let
${\displaystyle \mathbf {x} ={\begin{bmatrix}x_{1}\\x_{2}\\x_{3}\end{bmatrix}}}$
be the vector of unknowns, where ${\displaystyle x_{1},x_{2}}$ and ${\displaystyle x_{3}}$ is the amount of money Uno, Duo, and Traea owe, respectively. Describe the information above as a linear system in the form
${\displaystyle A\mathbf {x} =\mathbf {b} }$
(write ${\displaystyle A}$ and ${\displaystyle \mathbf {b} }$ with specific values).
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