Can’t figure this out, I keep getting it wrong

(3ab+2c)^3 what is the answer

svet-max [94.6K]

Answer:

$=27a^3b^3+54a^2b^2c+36abc^2+8c^3$

Step-by-step explanation:

$(3ab+2c)^3$

$=(3ab+2c)$ × $(3ab+2c)$ ×

$=(3ab+2c)(9a^2b^2+12abc+4c^2)$

$=(3ab)(9a^2b^2)+(3ab)(12abc)+(3ab)(4c^2)+(2c)(9a^2b^2)+(2c)(12abc)+(2c)(4c^2)$

$=27a^3b^3+36a^2b^2c+12abc^2+18a^2b^2c+24abc^2+8c^3$

$=27a^3b^3+54a^2b^2c+36abc^2+8c^3$

<em>hope this helps....</em>

5 0

2 years ago

A jeweler wants to make 14 grams of an alloy that is precisely 75% gold.. The jeweler has alloys that are 25% gold, 50% gold, &a

Goryan [66]

Given that the jeweler has alloys that are 25% gold, 50% gold, and 82% gold.

As he wants to make 14 grams of an alloy by adding two different alloys that is precisely 75% gold, so one alloy must have a percentage of gold more than 75%.

One alloy is 82% gold and, the second can be chosen between 25% gold, 50% gold, so there are two cases.

Case 1: 82% gold + 50% gold

Let x grams of 82% gold and y grams of 50% gold added to make x+y=14 grams of 75% gold, so

75% of 14 = 82% of x + 50% of y

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 50/100 \times y \\\\$

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 50/100 \times (14-x)$ [as x+y=14]

$\Rightarrow 75 \times 14 = 82 \times x + 50 \times (14-x) \\\\\Rightarrow 75 \times 14 = 82 \times x + 50 \times14-50\times x \\\\\Rightarrow 75 \times 14 = 32 \times x + 50 \times14 \\\\\Rightarrow 32 \times x =75 \times 14 - 50 \times14 \\\\$

$\Rightarrow x =(25 \times 14)/32=10.9375$ grams

and $y = 14-x= 14-10.9375=3.0625$ grams.

Hence, 10.9375 grams of 82% gold and 3.0625 grams of 50% gold added to make 14 grams of 75% gold.

Case 2: 82% gold + 25% gold

Let x grams of 82% gold and y grams of 25% gold added to make x+y=14 grams of 75% gold, so

75% of 14 = 82% of x + 25% of y

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 25/100 \times y \\\\\Rightarrow 75/100 \times 14 = 82/100 \times x + 25/100 \times (14-x) \\\\ \Rightarrow 75 \times 14 = 82 \times x + 25 \times (14-x) \\\\\Rightarrow 75 \times 14 = 82 \times x + 25 \times14-25\times x \\\\\Rightarrow 75 \times 14 = 57 \times x + 25 \times14 \\\\\Rightarrow 57 \times x =75 \times 14 - 25 \times14 \\\\$

$\Rightarrow x =(50 \times 14)/57=12.28$ grams

and $y = 14-x= 14-12.28=1.72$ grams.

Hence, 12.28 grams of 82% gold and 1.72 grams of 50% gold added to make 14 grams of 75% gold.

3 0

2 years ago

One student simplified x5 + x5 to x10 . A second student simplified x5 + x5 to 2x5 . Which student is correct? Explain.

dybincka [34]

An expression is defined as a set of numbers, variables, and mathematical operations. The second student is correct.

<h3>What is an Expression?</h3>

In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.

Given One student simplified x⁵ + x⁵ to x¹⁰. The second student simplified x⁵+x⁵ to 2x⁵. Since the simplification of (x⁵+x⁵) is equal to 2x⁵. Therefore, the second student is correct.

Learn more about Expression:

brainly.com/question/13947055

#SPJ1

5 0

1 year ago

2|4x-1|=38 I need to solve this

umka21 [38]

First you have to have the absolute value isolated so the 2 has to be divided. Then set up the two cases and solve.

5 0

3 years ago

Mark just received word that he scored 88% on a trigonometry test. Mark is also in an advanced algebra course. Is Mark's score o

katen-ka-za [31]

First off, it would not be C because there are no guidelines to score too high on a test
Then, D would also be wrong because since he scored high, it doesn't just mean that the test was easy.
Now it comes to the yes or no between A and B, since he is just one of the many students in Trigonometry, it cant be a very accurate representation therefore the answer to the problem would be A
Solution: A. No, because Mark is not representative of the population of the trigonometry class

4 0

3 years ago