Question

A baker used the expression LaTeX: 9\left(15\:+\:Y\right)9 ( 15 + Y ) to show the number of muffins he needed to make. Emily said the expression has the same value as LaTeX: 90\:+\:Y90 + Y. Is Emily correct? Explain your answer.

Answer 1

He wrongly distributed 9 over 15 and Y and got the wrong answer. The product of 9 and 15 is 135 not 90.

Explanation:

Given the expression used by baker to show the number of muffins he needed to make as
`9\left(15\:+\:Y\right)`, we are to check if the expression id equivalent to 90+Y

According to distributive law;

A(B+C) = AB + AC (This shows that A is distributed over B and C)

Applying distributive law on
`9\left(15\:+\:Y\right)`

`9(15+Y) = 9(15) + 9(Y)\\9(15+Y) = 135 + 9Y`

From the result gotten, we can see that Emily is wrong because he wrongly distributed 9 over 15 and Y and got the wrong answer. The product of 9 and 15 is 135 not 90.