Question

Help me with #22 please.

Answer 1

Write out the Eq. for slope:
$m= \frac{( y_{2} - y_{1} )}{( x_{2} - x_{1})}$

(-4,8) = (x1,y1)
(r, 12) = (x2,y2)
m=$\frac{4}{3}$

Use this information to plug into the slope equation:
$m= \frac{( y_{2} - y_{1} )}{( x_{2} - x_{1})}$
$\frac{4}{3} = \frac{( 12 - 8 )}{( r - (-4))}$
$\frac{4}{3} = \frac{( 4 )}{( r - (-4))}$



Since we want the bottom of the fraction =3 set r-(-4)=3 and solve
r-(-4)=3
r+4-4=3-4
r= -1

Answer 2

4/3 = (12 - 8) / (r+4)
4/3r + 16/3 = 4
4r + 16 = 12
4r = -4
r = -1

answer
G. -1