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