Answer:
89
Step-by-step explanation:

we evaluate when t=2

so it's 89 feet
1.8- 3.7x = 4.2x + 0.3
Move 4.2x to the other side
Sign changes from +4.2x to -4.2x
1.8-3.7x-4.2x= 4.2x-4.2x+0.3
1.8-3.7x-4.2x= 0.3
1.8-7.9x= 0.3
Move 1.8 to the other side
Sign changes from +1.8 to -1.8
1.8-1.8-7.9x= 0.3-1.8
-7.9x= 0.3-1.8
-7.9x= -1.5
divide both sides by -7.9
-7.9/-7.9x= -1.5/-7.9
x= 0.18987341
Answer: x= 0.18987341
7(3a + 12) = 168 ← ( divide both sides by 7 )
3a + 12 = 24 ← ( subtract 12 from both sides )
3a = 12 ← ( divide both sides by 3 )
a = 4
OR
distribute the parenthesis by 7
21a + 84 = 168 ← ( subtract 84 from both sides )
21a = 84 ← ( divide both sides by 21 )
a = 4