Question

McKenna was asked to write the following expression in standard form.
When writing the expression in standard form, McKenna made a mistake.
a. McKenna made her first mistake in .
b. The correct expression in standard form is .
3 − 5(3a + 6)
3 − 5(3a + 6)
3 + (−5)(3a + 6)
−2(3a + 6)
−6a + (−12)
−6a − 12
Step 1
Step 2
Step 3
Step 4

Answer 1

a) The step in which McKenna made her first mistake is given as follows: Step 4.

b) The correct simplified expression in standard form is given as follows: -15a - 15.

How to simplify the expression?

The expression in this problem is defined as follows:

3 − 5(3a + 6)

On the third step, the expression is given as follows:

3 + (−5)(3a + 6)

And on the fourth step, the expression is given as follows:

−2(3a + 6).

This is where the mistake happened, as the multiplication takes precedence over the subtraction.

Then to obtain the correct expression the first step is applying the distributive property, as follows:

3 − 5(3a + 6) = 3 - 15a - 18.

Then the like terms 3 and -18 are combined to obtain the correct simplified expression, as follows:

3 - 15a - 18 = -15a - 15.

More can be learned about the simplification of expressions at https://brainly.com/question/723406

#SPJ1