Answer:
The equation is 
The value of x is 28 cookies
Step-by-step explanation:
Let
x ----> the number of cookies she baked last week
we know that
The number of cookies she baked last week multiplied by 3 minus 4 must be equal to 80 cookies
so
The linear equation that represent this situation is

solve for x

Answer:
Step-by-step explanation:
You need to use the quadratic equation
x = 
Givens
x = 
x =( 5 +/- sqrt(25 - 12) ) / 2
x = (5 +/- sqrt(13) )/2
x = (5 + sqrt(13) / 2
x = 4.303 rounded
x = (5 - sqrt(13) ) /2
x = .6972
Dy/dx = dy/dt / dx/dt
dy/dx = 12x^2 + 4
when x = 2 , dydx = 52
52 = dy/dt / 3
so dy/dt = 156 (answer)
Answer:
x = 2 , 3/2
Step-by-step explanation: