Answer :

carol(66) = 2x - 20
x= mindy's height
66 = 2x - 20
add 20 on both sides
86 = 2x
divide by 2 on both sides
43 = x
Mindy's Height is 43 inches.
:P HOPE THIS HELPS
c=66
c=-20+2 times mindy
subsitute
66=-20+2m
add 20 to both sides
86=2m
divde by 2
43=mindy

mindy is 43 inches