Use p.e.m.d.a.s.
<span>first multiply 6Q and 8Q = 48Q
then subtract 58Q and 48Q = 10Q
</span>
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
5y= -6x+2
5y/5 =-6x/5 +2/5
y = -1.2x +0.4
the slope is -1.2 and y intercept is 0.4
