:explain what the pythagorean theorem is, and when it's used. then, create a problem that requires you to solve using the pythagorean theorem, and then solve the problem. (show all your work) lastly, give an example where you can use pythagorean theorem in real life. this question has 4 parts. answer all for full credit.

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil

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Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?