S=d/t so in this case it's 75/12 which is 6.25. Round it and you got 6 miles per hour.
Using Laplace transform we have:L(x')+7L(x) = 5L(cos(2t))sL(x)-x(0) + 7L(x) = 5s/(s^2+4)(s+7)L(x)- 4 = 5s/(s^2+4)(s+7)L(x) = (5s - 4s^2 -16)/(s^2+4)
=> L(x) = -(4s^2 - 5s +16)/(s^2+4)(s+7)
now the boring part, using partial fractions we separate 1/(s^2+4)(s+7) that is:(7-s)/[53(s^2+4)] + 1/53(s+7). So:
L(x)= (1/53)[(-28s^2+4s^3-4s^2+35s-5s^2+5s)/(s^2+4) + (-4s^2+5s-16)/(s+7)]L(x)= (1/53)[(4s^3 -37s^2 +40s)/(s^2+4) + (-4s^2+5s-16)/(s+7)]
denoting T:= L^(-1)and x= (4/53) T(s^3/(s^2+4)) - (37/53)T(s^2/(s^2+4)) +(40/53) T(s^2+4)-(4/53) T(s^2/s+7) +(5/53)T(s/s+7) - (16/53) T(1/s+7)
Answer:
x = 18.46
Step-by-step explanation:
Find the last angle of the triangle.
180-90-72 = 18
The cosine of an angle is equal to the ratio of the adjacent side to the hypotenuse.
cos(b) = adj/hyp
CosB=a/c rewrite to get
6/CosB (72) = 19.41
Find the last side of the triangle using the Pythagorean theorem.
b=square root c^2 - a^2
b=square root 376.99 - 36
b= 18.46
