Answer:
Step-by-step explanation:
If y = 2x + 1, then dy/dt = 2(dx/dt).
If y = 2x + 1, then y = 2(40) + 1 when 40 is substituted for x. y = 81.
(a) if dx/dt = 3, find dy/dt when x = 4:
Replacing dx/dt with 3 in dy/dt = 2(dx/dt) yields dy/dt = 2(3) = 6.
(b) if dy/dt = 2, find dx/dt when x = 40:
Replacing dy/dt with 2 in dy/dt = 2(dx/dt) results in 2 = 2(dx/dt), so dx/dt must be 1.
Answer:
Step-by-step explanation:
Converting yards to feet means that we want the label of yards to cancel, leaving feet as our label. Use the factor-label method taught in chemistry.
The yards label cancels out, leaving feet as our label. So to answer the question, in order to convert from yards to feet you are multiplying by 3.
If 3/8 equals 3 ft, then i would assume that 5/8 equals 5 ft.
y = 8 -2x
x + 2 (8 - 2x) = 1
x + 16 - 4x = 1
x - 4x = -15
-3x = -15
x = 5
If x = 5, then we can substitute in...
5 + 2y = 1
2y = -4
y = -2
Now let us check that by substituting those values in to the equation
2x + y = 8
2 (5) + (-2) = 8
That is correct so we have the right values for x and y/