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.
Answer:
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.
Answer:
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
Answer:
Given the expression 5x + 7
when x = -3
5(-3) + 7
= -15 + 7
= -8
Question 4.
-4x – 1 when x = 3
Answer:
Given the expression -4x – 1
when x = 3
-4(3) – 1
-12 – 1 = -13
Question 5.
3 – \(\frac{1}{2}\)x when x = -5
Answer:
Given the expression 3 – \(\frac{1}{2}\)x
when x = -5
3 – \(\frac{1}{2}\)(-5)
3 + \(\frac{5}{2}\)
Question 6.
\(\frac{3}{4}\)x – 2 when x = 7
Answer:
Given the expression \(\frac{3}{4}\)x – 2
when x = 7
\(\frac{3}{4}\)(7) – 2
\(\frac{21}{4}\) – 2