The answer should be Twenty one
Answer:
90
Step-by-step explanation:
4/15 which is our fraction distance/time
our other fraction is 24/x (x is our variable to find our time)
Now we are doing the buultterfly method
set it up
now multiply 4*x= 4x
15*24=360
now divide 4x ÷ 4 to get our variable alone
do the same to the other side
4 ÷ 360= 90
so x= 90 which is our missing number
Let's find the derivative of that hyperbola in order to find a slope formula to help us with this equation. We already have an x and y value. The derivative is found this way:

so

. The derivative supplies us with the slope formula we need to write the equation. Sub in the x value of 3 to find what the slope is:

. So in our slope-intercept equation, x = 3, y = 1, and m = -1/3. Use these values to solve for b.

so b = 2. The equation, then, for the line tangent to that hyperbola at that given point is
Answer:
josh vendió 17 libros recaudando 306 dolares .
jessica vendió 255 libros recaudando 4590 dolares.
Step-by-step explanation:
Sustituimos por variables :
libros que vendió Jessica = x
libros que vendió Josh = y
entonces:
x + y = 272
Jessica vendió 15 veces mas libros que josh:
x = 15y
Reemplazamos en la anteriior ecuacion:
15y +y = 272
16y = 272
y = 17
Reemplazamos en la primela ecuacion :
x + 17 = 272
x = 255