11.1k views
25 votes
With a detailed explanation from the internet
1/(x-5)+3/(x+2)=4

2 Answers

9 votes

Answer:


\boxed{ \sf x=(4\pm√(43))/(2)}

Step-by-step explanation:


\rightarrow \sf (1)/(x-5)+(3)/(x+2)=4

make the denominators same


\rightarrow \sf (1(x+2))/((x-5)(x+2))+(3(x-5))/((x+2)(x-5))=4

join the fractions together


\rightarrow \sf (x+2+3x-15)/((x-5)(x+2))=4

cross multiply


\rightarrow \sf x+2+3x-15=4(x-5)(x+2)

simplify


\rightarrow \sf 4x-13=4x^2-12x-40

group the variables


\rightarrow \sf 4x^2-16x-27 = 0

use quadratic formula


\rightarrow \sf x = (-\left(-16\right)\pm √(\left(-16\right)^2-4\cdot \:4\left(-27\right)))/(2\cdot \:4)

simplify the following


\rightarrow \sf x=(4\pm√(43))/(2)

User Fastcall
by
8.3k points
7 votes

Answer:


x=(4 \pm √(43))/(2)

Step-by-step explanation:

Given equation:


(1)/((x-5))+(3)/((x+2))=4

Make the denominators of the algebraic fractions the same, then combine them into one fraction:


\begin{aligned}\implies (1)/((x-5)) \cdot ((x+2))/((x+2))+(3)/((x+2))\cdot ((x-5))/((x-5)) & =4\\\\\implies (x+2)/((x-5)(x+2))+(3(x-5))/((x-5)(x+2)) & = 4\\\\ \implies (x+2+3(x-5))/((x-5)(x+2)) & = 4\\\\ \implies (4x-13)/((x-5)(x+2)) & = 4 \end{aligned}

Multiply both sides of the equation by
(x-5)(x+2):


\begin{aligned}\implies ((4x-13))/((x-5)(x+2))\cdot (x-5)(x+2) & = 4(x-5)(x+2)\\\\((4x-13)(x-5)(x+2))/((x-5)(x+2)) & = 4(x-5)(x+2)\\\\4x-13 & = 4(x-5)(x+2)\\\\4x-13 & =4x^2-12x-40\\\\4x^2-16x-27 & = 0\end{aligned}

Solve using the Quadratic Formula:


x=(-b \pm √(b^2-4ac) )/(2a)\quad\textsf{when}\:ax^2+bx+c=0


\implies a=4\\\implies b=-16\\\implies c=-27

Therefore:


\implies x=(-(-16) \pm √((-16)^2-4(4)(-27)) )/(2(4))


\implies x=(16 \pm √(688))/(8)


\implies x=(16 \pm 4 √(43))/(8)


\implies x=(4 \pm √(43))/(2)

User Chuckx
by
8.8k 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