When using substitution to solve this system of equations, what is the result of the first step x=6y+3 x+2y=5

Given that (x-3) is a factor of f(x)=x^3+ax^2-x-6, find a and hence the number of real roots or the equation f(x)=0

Acylinder and its dimensions are shown. which equation can be used to find v, the volume of the cylinder in cubic centimeters?

Arestaurant chef made 1 1/2 jars of pasta sauce. each serving of pasta requires 1/2 of a jar of sauce. how many servings of pasta will the chef be bale to prepare using the sauce?