Question 67992
-9=9(9-5t)
 
-9=91-45t [use the distributive property]
-9+9=81+9-45t [solve for t]
0=90-45t
0+45t=90-45t+45t
45t=90
45t/45=90/45
t=2
.
checking by plugging t=2 back into the original formula:
-9=9(9-5t)
-9=9(9-5(2))
-9=9(9-10)
-9=9(-1)
-9=-9 [checks out]