+0

0
55
3
+248

Solve for r: $$\frac{r+3}{r-2} = \frac{r-1}{r+1}.$$

Thanks!

Jun 10, 2019

#1
+2

Solve for r:
(r + 3)/(r - 2) = (r - 1)/(r + 1)

Cross multiply:
(r + 1) (r + 3) = (r - 2) (r - 1)

Expand out terms of the left hand side:
r^2 + 4 r + 3 = (r - 2) (r - 1)

Expand out terms of the right hand side:
r^2 + 4 r + 3 = r^2 - 3 r + 2

Subtract r^2 - 3 r + 2 from both sides:
7 r + 1 = 0

Subtract 1 from both sides:
7 r = -1

Divide both sides by 7:

r = -1/7

Jun 10, 2019
#2
+248
+2

Thanks!

sinclairdragon428  Jun 10, 2019
#3
+721
+2

(r+3)/(r-2)=(r-1)(r+1)

(r+3)(r+1)=(r-1)(r-2)

r^2+4r+3=r^2-3r+2

7r=-1

r=-1/7

You are very welcome!

:P

Jun 10, 2019