If their $14,369 bid includes $8670 for lumber, What percent of the bid was the lumber? Round to the nearest 10th of a percent

Y=4x+4 could also be written as f(x)=4x+4 since y is a function. You can see this in graphs as y is represented or labeled as f(x) when graphing. This could easily be understood and solved especially if you have the value of x in equations. Let us take the above-mentioned equation as an example. x=1 therefore f(3)=4(3)+4 is equals to f(x) or y= 5.333 

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