Question

Practice Question 5
5.1 Solve the following equations by isolating the variable:
(a) a + 24 = 24
(b) 8-2z = 5 - 5z
14x - 12
2
= 43
(c)
(d) 8d - 16 = 48
(e) 7y - 9 = 4y - 6
(f)
77
7
48y - 26y - 55
5.2 Ifk + 7 = 16, what is the value of 8k - 72?
5.3 If 2y + 3 = 5, what is the value of 3y + 2?​

Answer 1

Step-by-step explanation:

5.1

A) solution

a + 24 = 24

collect like terms

a = 24-24

a = 0

B) solution

8 - 2z = 5- 5z

collect the like terms

8 - 5 = -5z + 2z

3 = -3z

divide both sides by 3

3/3 = -3z/3

1 = z

switch

z = 1

C) solution

14x - 12/2 = 43

cross multiply

14x - 12/2 = 43/1

14x - 12 = 12 × 43

14x - 12 = 516

collect like terms

14x = 516 + 12

14x = 528

divide both sides by 14

14x/14 = 528/14

x = 37.7

D) solution

8d - 16 = 48

8d = 48-16

8d = 32

8d/8 = 32/8

d = 4

E) solution

7y - 9 = 4y - 6

collect like terms

7y - 4y = -6 + 9

3y = 3

3y/3 = 3/3

y = 1

F) solution

77/7 = 48y - 26y - 55/1

cross multiply

7(48y - 26y - 55) = 77

simplify

336y - 182y -385 = 77

collect like terms

336y - 182y = 77 + 385

154y = 462

154y/154 = 462/154

y = 154

5.2 solution

k + 7 = 16

collect like terms

k = 16 - 7

k = 9

substitute the value of k into 8k - 72

8(9) - 72

72 - 72

= 0

5.3 solution

2y + 3 = 5

collect like terms

2y = 5 - 3

2y = 2

divide both sides by 2

2y/2 = 2/2

y = 1

substitute the value of y into 3y + 2

3(1) +2

3 + 2

= 6