Question

Tell whether the given number is a solution of each question. ( Must show work for credit)

1. 9 = 2a + 3; 3


2. 5n - (-30) = 5; 7


3. 4.4r - 2.8 = 1.6; 1​

Answer 1

Answer/Step-by-step explanation:

1.
`9 = 2a + 3` ; 3

Let's solve for a.

`9 - 3 = 2a` (subtraction property of equality)

`6 = 2a`

`(6)/(2) = a` (division property of equality)

`3 = a`

`a = 3`

Therefore, 3 is a solution to 9 = 2a + 3

2.
`5n - (-30) = 5` ; 7

`5n + 30 = 5` (- × - = +)

`5n = 5 - 30` (Subtraction property of equality)

`5n = -25`

`(5n)/(5) = (-25)/(5)` (division property of equality)

`n = -5`

Therefore, 7 is not a solution of
`5n - (-30) = 5`

3.
`4.4r - 2.8 = 1.6` ; 1

`4.4r = 1.6 + 2.8`

`4.4r = 4.4`

`(4.4r)/(4.4) = (4.4)/(4.4)`

`r = 1`

Therefore, 1 is a solution of
`4.4r - 2.8 = 1.6`.