Practice the problems of Math in Focus Grade 8 Workbook Answer Key Chapter 6 Functions to score better marks in the exam.

## Math in Focus Grade 8 Course 3 A Chapter 6 Answer Key Functions

### Math in Focus Grade 8 Chapter 6 Quick Check Answer Key

Write an algebraic expression for each of the following.

Question 1.
Benedict has 7 packs of cards. Each pack has x cards. He gives 3 cards to his sister. Write an algebraic expression for the number of cards that he has left.
Given,
Benedict has 7 packs of cards.
Each pack has x cards.
He gives 3 cards to his sister.
7x – 3
Thus the algebraic expression for the number of cards that he has left is 7x – 3.

Question 2.
y highlighters are shared equally among 9 students. One of the students, Jessie, then buys another 3 highlighters. Write an algebraic expression for the number of highlighters she has in total.
Given,
y highlighters are shared equally among 9 students.
One of the students, Jessie, then buys another 3 highlighters.
y/9 + 3

Evaluate each expression for the given value of the variable.

Question 3.
5x + 7 when x = -3
Given the expression 5x + 7
when x = -3
5(-3) + 7
= -15 + 7
= -8

Question 4.
-4x – 1 when x = 3
Given the expression -4x – 1
when x = 3
-4(3) – 1
-12 – 1 = -13

Question 5.
3 – $$\frac{1}{2}$$x when x = -5
Given the expression 3 – $$\frac{1}{2}$$x
3 – $$\frac{1}{2}$$(-5)
3 + $$\frac{5}{2}$$
$$\frac{3}{4}$$x – 2 when x = 7
Given the expression $$\frac{3}{4}$$x – 2
$$\frac{3}{4}$$(7) – 2
$$\frac{21}{4}$$ – 2