131k views
2 votes
Evaluate the expression 12-3y\2 + y(2y-4\y) for y =3​

1 Answer

4 votes

Answer:

43/2

Explanation:

Evaluate 12 - (3 y)/2 + y (2 y - 4/y) where y = 3:

12 - 3 y/2 + y (2 y - 4/y) = 12 - 3×3/2 + 3 (2×3 - 4/3)

Hint: | Express -3×3/2 as a single fraction.

-3×3/2 = (-3×3)/2:

12 + (-3×3)/2 + 3 (2×3 - 4/3)

Hint: | Multiply 2 and 3 together.

2×3 = 6:

12 - (3×3)/2 + 3 (6 - 4/3)

Hint: | Multiply -3 and 3 together.

-3×3 = -9:

12 + (-9)/2 + 3 (6 - 4/3)

Hint: | Put the fractions in 6 - 4/3 over a common denominator.

Put 6 - 4/3 over the common denominator 3. 6 - 4/3 = (3×6)/3 - 4/3:

12 - 9/2 + 3 (3×6)/3 - 4/3

Hint: | Multiply 3 and 6 together.

3×6 = 18:

12 - 9/2 + 3 (18/3 - 4/3)

Hint: | Subtract the fractions over a common denominator to a single fraction.

18/3 - 4/3 = (18 - 4)/3:

12 - 9/2 + 3 (18 - 4)/3

Hint: | Subtract 4 from 18.

| 1 | 8

- | | 4

| 1 | 4:

12 - 9/2 + 3×14/3

Hint: | Express 3×14/3 as a single fraction.

3×14/3 = (3×14)/3:

12 - 9/2 + (3×14)/3

Hint: | Cancel common terms in the numerator and denominator of (3×14)/3.

(3×14)/3 = 3/3×14 = 14:

12 - 9/2 + 14

Hint: | Put the fractions in 12 - 9/2 + 14 over a common denominator.

Put 12 - 9/2 + 14 over the common denominator 2. 12 - 9/2 + 14 = (2×12)/2 - 9/2 + (2×14)/2:

(2×12)/2 - 9/2 + (2×14)/2

Hint: | Multiply 2 and 12 together.

2×12 = 24:

24/2 - 9/2 + (2×14)/2

Hint: | Multiply 2 and 14 together.

2×14 = 28:

24/2 - 9/2 + 28/2

Hint: | Add the fractions over a common denominator to a single fraction.

24/2 - 9/2 + 28/2 = (24 - 9 + 28)/2:

(24 - 9 + 28)/2

Hint: | Evaluate 24 + 28 using long addition.

| 1 |

| 2 | 8

+ | 2 | 4

| 5 | 2:

(52 - 9)/2

Hint: | Subtract 9 from 52.

| 4 | 12

| 5 | 2

- | | 9

| 4 | 3:

Answer: 43/2

User Soyini
by
8.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories