Can you explain to me how to solve the following problem?
Isaac bought school shirts for $35 each and school pants for $49 each. If he buys 9 items and his total cost is $357, how many shirts did he buy? I solved it with trial and error, but I know there is an algebraic method. Thank you.
Make a system of two equations. Let the variables represent what you do not know, the number of shirts and
the number of pants. x = number of shirts y = number of pants x + y = 9 {he buys 9 items} 35x + 49y = 357 {shirts are $35 each, pants are $49 each, the total is 357} Use the elimination method to solve the system, multiplying the top equation by 35, and then adding the two equations together. This will eliminate the x. You could also multiply the top equation by 49 and add together, or even use the substitution method. 35x  35y = 315 {multiplied first equation by 35} 35x + 49y = 357 {second equation stays the same}  14y = 42 {added the two equations together} y = 3 {divided each side by 14} x + y = 9 {first original equation} x + 3 = 9 {substituted 3, in for y, into first equation} x = 6 {subtracted 3 from each side} He bought 6 shirts and 3 pants Ask Algebra House
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