How do you solve \frac { 4} { x - 3} = \frac { x + 5} { 5} ]4x3=x+55]?

1 Answer
Jan 11, 2018

x_1=5x1=5 and x_2=-7x2=7

Explanation:

4/(x-3)=(x+5)/54x3=x+55

Perform this
4/(x-3) 4x3χ (x+5)/5x+55

<=> 4*5=(x-3)(x+5)45=(x3)(x+5) <=>

20=x^2+5x-3x-15 <=>20=x2+5x3x15

x^2+2x-35=0x2+2x35=0

Discriminant will be Δ=b^2-4ac=4-4*1*(-35)=140+4=144

x_(1,2)=(-b+-sqrt(Δ))/(2α) so

x_1=(-2+12)/2=5

x_2=(-2-12)/2=-14/2=-7

As a result the roots are x_1=5 and x_2=-7