13,886
365
719,463
40,047,209
2,145,739,180
1,783,457
The f(9) = 1
first you plug in 9, where x is
f(9) = 2/3(9) - 5
multiply
f(9) = 6 - 5
subtract
and you should get f(9) = 1
1.) C(t) = -0.30(t - 12)^2 + 40
for t = 12: C(12) = -0.30(12 - 12)^2 + 40 = -0.30(0)^2 + 40 = 40°C
For t = 24: C(24) = -0.30(24 - 12)^2 + 40 = -0.30(24 - 12)^2 + 40 = -0.30(12)^2 + 40 = -0.30(144) + 40 = -43.2 + 40 = -3.2°C
4.) F(t) = 9/5 C(t) + 32
for C(t) = 40°C: 9/5 (40) + 32 = 72 + 32 = 104°F
for C(t) = -3.2°C: 9/5(-3.2) + 32 = -5.76 + 32 = 26.24°F
5.) F(t) = 9/5 C(t) + 32 = 9/5 (-0.30(t - 12)^2 + 40) + 32 = -0.54(t - 12)^2 + 72 + 32 = -0.54(t - 12)^2 + 104
Answer:
0.95
(Don't have paper, because I accidentally threw away paper )