Tag: using equations to plot lines

Questions Related to using equations to plot lines

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

The nearest point on the line $3x-4y=25$ from the origin is

  1. $(-4,5)$
  2. $(3,-4)$
  3. $(3,4)$
  4. $(3,5)$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Distance of the line $3x-4y-25=0$ from the origin is 
$\displaystyle d=\frac{|-25|}{\sqrt{25}}$
$\Rightarrow d=5$
Only the point given in option B lies on the given line .
Also, its distance from origin is 5.
So, (3,-4) is the nearest point on the line from the origin.

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

Consider the lines $2x+3y=0$,    $5x+4y=7$. Find the intersection point.

  1. $(3,-2)$
  2. $(3,2)$
  3. $(-3,2)$
  4. $(2,3)$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The lines are $2x+3y=0$......(1)


$x=\dfrac{-3y}{2}$

$5x+4y=7$........(2)

$5\left(\dfrac{-3y}{2}\right)+4y=7$

$-15y+8y=14$

$-7y=14$

$y=-2$

$x=\dfrac{-3(-2)}{2}=3$

$(x,y)=(3,-2)$

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

$y=2x+3$
Which of the following statements is true about the given line?

  1. The line passes through $(0,3)$ and $m=-2$
  2. The line passes through $(3,0)$ and $m=-2$
  3. The line passes through $(0,3)$ and $m=2$
  4. The line passes through $(3,0)$ and $m=2$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Comparing the given equation $y=2x+3$ with $y = mx+c$, we get

Hence, $m=2$ and $c=3$.
So, options A and B are incorrect.

Option C:
Substitute $(0,3)$ in the given equation, we get
RHS: $=2(0)+3 = 3$
LHS: $y=3$
$LHS =  RHS$, Hence option C is correct.

Option D:
Substitute $(3,0)$ in the given equation, we get
RHS: $=2(3)+3 = 9$
LHS: $y=0$

$LHS \neq RHS$. Hence, option D is incorrect.

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

Consider the equation of the line :$\displaystyle \frac{x-1}{3}-\frac{y+2}{2}=0$

  1. The line passes through $(4,0)$ and $m=2/3$
  2. The line passes through $(4,0)$ and $m=-2/3$
  3. The line passes through $(4,0)$ and $m=3/2$
  4. The line passes through $(4,0)$ and $m=-3/2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Given line 
$\dfrac{x-1}{3}-\dfrac{y+2}{2}=0$

$\dfrac{x-1}{3}=\dfrac{y+2}{2}$

$2(x-1)=3(y+2)$

$2x-2=3y+6$

$y=\dfrac{2x}{3}-\dfrac{8}{3}$

on comparing above eq with $y=mx+c$

$slope(m)=\dfrac{2}{3}$

y-intercept$=-\dfrac{8}{3}$

when $y=0,x=4$

Hence it passes through $(4,0)$ with $m=\dfrac{2}{3}$
Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

Consider the line: y= -x +4

Which of the following is correct.

  1. The line passes through (0,4) and m=1.

  2. The line passes through (0,4) and m=-1.

  3. The line passes through (0,0) and m=-1.

  4. The line passes through (4,0) and m=-1.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Given line 
$y=-x+4$
on comparing above eq with $y=mx+c$
$slope(m)=-1$
y-intercept$=4$
Hence it passes through (0,4) with $m=-1$
Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

Draw the graph for each linear equation:
$\displaystyle y=\frac{3}{2}x+\frac{2}{3}$

  1. The line passes through $(4/9,0)$ and $m=-\dfrac32$
  2. The line passes through $(-0.4/9,0)$ and $m=\dfrac32$
  3. The line passes through $(-4/9,0)$ and $m=\dfrac32$
  4. The line passes through $(-0.9/4,0)$ and $m=-\dfrac32$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The given line equation is $\frac{3}{2}x-y+\frac{2}{3}$

The slope of given line is $-(\frac { \frac { 3 }{ 2 }  }{ -1 } )=\frac { 3 }{ 2 } $
If we put $y=0$ , then the value of $x= -\frac{4}{9}$
Therefore line passes through $(-\frac{4}{9},0)$ and slope is $\frac{3}{2}$
So the correct option is $C$

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

Consider the equation of the line $\displaystyle x-3=\frac{2}{5}\left ( y-1 \right )$. Which of the following is correct?

  1. The line passes through $(6,5)$ and $m=-2/5$.
  2. The line passes through $(5,6)$ and $m=-5/2$.
  3. The line passes through $(6,5)$ and $m=2/5$.
  4. The line passes through $(5,6)$ and $m=5/2$.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Given line 
$x-3=\dfrac{2}{5}(y-1)$
$5(x-3)=2(y-1)$
$5x-15=2y-2$
$2y=5x-13$
$y=\dfrac{5x}{2}-\dfrac{13}{2}$
on comparing above eq with $y=mx+c$
$slope(m)=\dfrac{5}{2}$

when $x=5$
$2y=25-13$
$2y=12$
$y=6$
Hence it passes through (5,6) with $m=\dfrac{5}{2}$
Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

For the pair of linear equations given below, draw graph and then state, whether the lines drawn are,
$\displaystyle y=3x-1$
$\displaystyle \frac{x}{2}+\frac{y}{3}=1$

  1. Perpendicular

  2. Parallel

  3. Intersecting but not at right angles

  4. Options B & C

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The first line is y = 3x - 1 (slope m1 = 3). The second line x/2 + y/3 = 1 can be rewritten as y = -3/2x + 3 (slope m2 = -3/2). Since m1 is not equal to m2 and their product is not -1, the lines intersect but are not perpendicular.

Multiple choice maths banking and taxation reading graphs describing different situations using equations to plot lines basics of a straight line

For the pair of linear equations given below, draw graphs and then state, whether the lines drawn are 
$\displaystyle 3x+4y=24$
$\displaystyle \frac{x}{4}+\frac{y}{3}=1$

  1. intersecting but not at right anglesl

  2. Options B & D

  3. perpendicular

  4. parallel

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The first line 3x + 4y = 24 has a slope of -3/4. The second line x/4 + y/3 = 1 can be rewritten as 3x + 4y = 12, which also has a slope of -3/4. Since the slopes are equal but the intercepts are different, the lines are parallel.