Question

Priya is simplifying the expression $$ Her work is shown to the left. Priya's work is incorrect. Explain the error she made

Answer 1

Explanation:

P.S - The exact question is -

Given - Priya is simplifying the expression -2(4 - 2x) - 3 - 2x Her work is shown to the left.

To find - Priya's work is incorrect. Explain the error she made.

Proof -

Priya simplified the problem as follows :

-2( 4 - 2x ) - 3 - 2x

-8 - 2x - 3 - 2x

-11 - 4x

But the simplification has to be like

-2( 4 - 2x ) - 3 - 2x

⇒-2(4) - 2(-2x) - 3 - 2x

⇒-8 + 4x - 3 - 2x

⇒-8 - 3 + 4x - 2x

⇒-11 + 2x

So, Priya made an error in the second line.

In the second line it has to be -8 + 4x - 3 - 2x but Priya has written -8 - 2x - 3 - 2x.