All categories

3 years ago

Why do we use the distributive property when subtracting expressions?

Mathematics

2 answers:

pochemuha3 years ago

3 0

Consider the example

(3x+5) - (x-10)

When we subtract off the (x-10), we are basically subtracting off x and also subtracting off -10. This is the same as adding on 10 because -(-10) = 10

So we would have these steps

(3x+5)-(x-10)

3x+5-x+10

2x+15

Often students forget to distribute the negative all the way through and would have 3x+5-x-10 as an incorrect step. You need to multiply that -1 through to each term, so that's why the distributive property is used.

Neko [114]3 years ago

3 0

distributive properties of addition and
subtraction can be used to rewrite
expressions for a variety of purposes. In
each case, you are distributing the outside
multiplier to each number in the
parentheses, so that multiplication occurs
with each number before addition or
subtraction occurs.

You might be interested in

10. The coordinates of C and D are 4 and -28 respectively, and F mdpt CD. Solve for:

Zigmanuir [339]

Answer:

a) mCD=7

b) mCF=7

c) mFD=7

d) F(2,-14)

Step-by-step explanation:

Let the coordinates of C and D be (4,0) and (0,-28) respectively and F is the midpoint of CD

a) mCD

Slope formula

$m= \frac{y_2-y_1}{x_2-x_1}$

$m= \frac{-28-0}{0-4}$

$m= \frac{-28}{-4}$

$m= 7$

mCD=7

b) mCF

mCF=mCD

Hence mCF=7

c) mFD

mFD=mCD

Hence mFD=7

d) Coordinates of F : mid point formula

Mid points Formula

$x= \frac{x_2+x_1}{2}$

$x= \frac{0+4}{2}=\frac{0+4}{2}=2$

$y= \frac{y_2+y_1}{2}=\frac{-28+0}{2}=\frac{-28}{2}=-14$

coordinates of F are (2,-14)

5 0

3 years ago

An article suggests that substrate concentration (mg/cm3) of influent to a reactor is normally distributed with μ = 0.50 and σ =

Delvig [45]

Answer:

0.1056 = 10.56% probability that the concentration exceeds 0.60

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 0.5, \sigma = 0.08$

What is the probability that the concentration exceeds 0.60?

This is 1 subtracted by the pvalue of Z when X = 0.6. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{0.6 - 0.5}{0.08}$

$Z = 1.25$

$Z = 1.25$ has a pvalue of 0.8944

1 - 0.8944 = 0.1056

0.1056 = 10.56% probability that the concentration exceeds 0.60

6 0

3 years ago

What is the least amount of surface area possible on the rectangular prism with the volume of 64 in.³ with work

pychu [463]

Knowing that an optimal shape is a cube is critical to solving this problem. With you now having that in mind, each side of the cube has a length of 4 inches. So the area of 1 face is 16 square units and the total surface area is 96 square units.

3 0

3 years ago

Jorge is attending college next year. He just got information on the college costs and the financial aid package the college is

Ksivusya [100]

Answer:the answer is 11,500.

8 0

3 years ago

The formula for calculating annual insurance premiums is

Ulleksa [173]

The formula for calculating the annual insurance is D. p= 2rb

8 0

3 years ago