The cost, c, in millions of dollars of producing t million tons of steel is modeled by the equation c = 220t + 1890.

solve the equation for t.

the steel produced is expected to be sold at a price of $310 per ton. write and solve an equation to find the amount of steel produced if the selling price is equal to the cost of production.

C = 220T + 1890.

Solve the equation for T.

220T = C - 1890

T = C/220 - 8.6

The steel produced is expected to be sold at a price of $310 per ton.

310 $/ton is a rate or slope. Write a linear equation where x is tons of steel produced and y is selling price of the steel.

y = 310x

Write and solve an equation to find the amount of steel produced if the selling price is equal to the cost of production.

* Here, note that the cost of production and tons of steel in the first equation is in the millions.  The equation we just wrote for the selling price was in x tons of steel. This only matters in regards to the units you specify because; million/million = 1

The unit multiplier of all variables must be specified as same. Either everything is in millions or not.

Here, I'll leave everything in millions, change x (tons of steel) to T (mill tons steel) and "y" to "S" in million dollars selling price.

S = 310T

Set equal to Cost equation.

220T + 1980 = 310T

Solve for T, million tons of steel produced.

1980 = 310T - 220T

1980 = 90T

T = 1980/90

T = 22 million tons steel produced

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3