Practice the problems of Math in Focus Grade 6 Workbook Answer Key Chapter 9 The Coordinate Plane to score better marks in the exam.

## Math in Focus Grade 6 Course 1 B Chapter 9 Answer Key The Coordinate Plane

### Math in Focus Grade 6 Chapter 9 Quick Check Answer Key

**Use the coordinate plane below.**

Question 1.

Give the coordinates of points B, C, and D.

Answer:

Point B:

The first coordinate represents distance along x axis which is 3 and the second coordinate represents distance along y axis which is 3.

So, the point P will be (3,3).

Point C:

The first coordinate represents distance along x axis which is 1 and the second coordinate represents distance along y axis which is 4.

So, the point C will be (1,4).

Point D:

The first coordinate represents distance along x axis which is 5 and the second coordinate represents distance along y axis which is 2.

So, the point D will be (5,2).

**Use graph paper. Plot the points on a coordinate plane.**

Question 2.

P (3, 2), Q (2, 3), and R (0, 4)

Answer:

To plot point P (3, 2):

Here, the x-coordinate is 3 and the y-coordinate is 2. Start at the Origin. As the x coordinate is positive, move 3 units along the positive x-axis and 2 units along positive y -axis.

Thus, the required point P (3, 2) is marked.

To plot point Q (2, 3):

Here, the x-coordinate is 2 and the y-coordinate is 3. Start at the Origin. As the x coordinate is positive, move 2 units along the positive x-axis and 3 units along positive y -axis.

Thus, the required point P (2, 3) is marked.

To plot point R (0, 4):

Here, the x-coordinate is 0 and the y-coordinate is 4. As the y coordinate is positive, move 5 units along the positive y-axis and mark it.

Thus, the required point(0, 4) is marked

**Identify the number that each indicated point represents.**

Question 3.

Answer:

To the left of the origin, the x coordinate values will be negative.

Start counting from the origin and note down the values.

The first value will be -1, next will be -4, -6 and -8.

**Draw a horizontal number line to represent each set of numbers.**

Question 4.

-3, 0, 1, 5, 8

Answer:

-3 is the negative value; therefore mark it to the left of the origin.

0 is the origin. 1,5,8 are the positive values, which are to be marked to the right of the origin.

Question 5.

-15, -11, -9, -7, -2

Answer:

Here, all are negative values. Hence all the values are to be marked to the left of the origin.

**Use the symbol || to write the absolute values of the following numbers.**

Question 6.

11

Answer:

The distance of an integer from ‘

$0$

‘ on the number line irrespective of its direction is called the absolute value of that integer.

Two vertical bars ‘| |’ are used to denote the absolute value.

The absolute value of any positive number is the number itself.

Therefore, the absolute value of 11 will be 11.

Question 7.

-16

Answer:

The absolute value of negative number is the positive of it.

Therefore, the absolute value of -16 or |-16| will be 16.

Question 8.

-21

Answer:

The absolute value of negative number is the positive of it.

Therefore, the absolute value of -21 or |-21| will be 21.

**Find the perimeter of each polygon.**

Question 9.

Figure ABC is an isosceles triangle.

Answer:

Given triangle ABC has two equal sides, thus it will form an isosceles triangle.

The triangle will measure 8 in, 8 in and 5 in.

Perimeter of the triangle will be the sum of all sides, 8+8+5 = 21 in

Question 10.

Figure DEFis an equilateral triangle.

Answer:

Given DEF is an equilateral triangle. Equilateral trinagle will have all equal sides.

All sides of the triangle will measure 4 in.

Perimeter of the triangle will be the sum of all sides, 4+4+4 = 12 in

Question 11.

Figure PQRS is a trapezoid.

Answer:

Given figure PQRS is a trapezoid. One of the pair of opposite sides are equal in length.

The trapezoid measures 16cm,10cm and 9cm.

Perimeter of the trapezoid will be the sum of all sides, 16+10+9+9 = 44cm

Question 12.

Figure WXYZ is a parallelogram.

Answer:

Given figure WXYZ is a parallelogram. The opposite sides are equal in length.

The parallelogram measures 8cm and 7cm.

Perimeter of the parallelogram will be the sum of all sides, 8+7+8+7 = 30cm

Question 13.

Figure JKLM is a rhombus.

Answer:

Given figure JKLM is a rhombus. All the sides are equal in length.

Each side will measure 6m in length.

Perimeter of the rhombus will be the sum of all sides, 6+6+6+6 = 24cm