259,742 views
19 votes
19 votes
Find the sum 3x^2/x-8 + 6x/x-8

User Benelgiac
by
2.6k points

1 Answer

16 votes
16 votes

Answer:

Explanation:

STEP

1

:

x

Simplify —

x

Equation at the end of step

1

:

(3•(x2))

————————+((6•1)-8)

(x-8)

STEP

2

:

Equation at the end of step

2

:

3x2

——————— + -2

(x - 8)

STEP

3

:

3x2

Simplify —————

x - 8

Equation at the end of step

3

:

3x2

————— + -2

x - 8

STEP

4

:

Rewriting the whole as an Equivalent Fraction

4.1 Adding a whole to a fraction

Rewrite the whole as a fraction using (x-8) as the denominator :

-2 -2 • (x - 8)

-2 = —— = ————————————

1 (x - 8)

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

4.2 Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

3x2 + -2 • (x-8) 3x2 - 2x + 16

———————————————— = —————————————

1 • (x-8) 1 • (x - 8)

Trying to factor by splitting the middle term

4.3 Factoring 3x2 - 2x + 16

The first term is, 3x2 its coefficient is 3 .

The middle term is, -2x its coefficient is -2 .

The last term, "the constant", is +16

Step-1 : Multiply the coefficient of the first term by the constant 3 • 16 = 48

Step-2 : Find two factors of 48 whose sum equals the coefficient of the middle term, which is -2 .

-48 + -1 = -49

-24 + -2 = -26

-16 + -3 = -19

-12 + -4 = -16

-8 + -6 = -14

-6 + -8 = -14

User Carlos Rodriguez
by
2.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.