2.1

Question 1

Which equation is linear ?

$\sqrt{3}x+1=0$

$3^x+19=2y$

$y+3x^2=-4$

$-5\frac{y}{x}=x$

Question 2

What are the solutions of this equation ?

$0x+100=0$

$\{ \}$

$\{0 \}$

$\{-100 \}$

infinitely many solutions

Question 3

What are the solutions of this equation ?

$2x+1x=6x-x$

infitely many solutions

$\{ 0 \}$

$\{-1\}$

$\{\}$

Question 4

What are the solutions of this equation ?

$10x + 2y =18$

$\{(1,4)\}$

infinitely many solutions

$\{\}$

$\{(2,-1)\}$

Question 5

What are the solutions of this system ?
$\left\{ \begin{array}{ r@{~}c@{~} r!{~} } -1x+1y & = & 4 \\ -2x+2y & = & 4 \\ \end{array} \right.$

infinitely many solutions

$\{\}$

$\{(0,4)\}$

$\{(-2,1)\}$

Question 6

What are the points the lines $d_1$ and $d_2$ intersect each other at ?
$\begin{array}{ c r@{~}c@{~} r!{~} } d_1 : & y &=& 2x+ 6 \\ d_2 : & y &=&-5x -1 \\ \end{array}$

$\{\}$

infinitely many points

$\{(1,-6)\}$

$\{(-1,4)\}$

Question 7

What are the points the planes $p_1$, $p_2$, $p_3$ intersect each other at ?
$\begin{array}{ c r@{~}c@{~} r!{~} } p_1 : & x+2y -2z+1 &=& 0 \\ p_2 : & -x+3y-3z-1 &=& 0 \\ p_3 : & -2x+y+4z+2 &=& 0 \\ \end{array}$

$\{(-5,-2,-4)\}$

$\{\}$

$\{(-1,\frac{-4}{5},\frac{-4}{5})\}$

infinitely many points