Question

Which equation is an identity?

a. 11- (2v + 3) = -2v - 8
b. 5w + 8 - w = 6w - 2( w - 4)
c. 7m - 2 = 8m + 4 - m
d. 8y + 9 = 8y - 3

Answer 1

5w + 8 - w = 6w - 2(w - 4)

Hope this helps :)

Answer 2

Option b -
`5w + 8 - w = 6w - 2( w - 4)`

Explanation:

To find : Which equation is an identity?

Solution :

Option a -
`11- (2v + 3) = -2v - 8`

If we open the parenthesis,

`11- 2v -3 = -2v - 8`

`-2v+8\\eq -2v - 8`

No identity applied.

Option b -
`5w + 8 - w = 6w - 2( w - 4)`

If we apply distributive property,
`a(b+c)=ab+ac`

`5w + 8 - w = 6w - 2w+8`

`4w+8= 4w+8`

Distributive identity is applied.

Option c -
`7m - 2 = 8m + 4 - m`

Solve by subtracting in RHS

`7m - 2 \\eq 7m + 4`

No identity applied.

Option d-
`8y + 9 = 8y - 3`

This is not possible as
`8y + 9 \\eq 8y - 3`

No identity applied.

Therefore, Option b is correct.