After school, marcus can walk 1 mile to the library in about the same time he can bike 2.5 miles to the sporting goods store. his speed on the bike is 6 mi/h faster than his walking speed. what is marcus' walking speed?

Can someone answer this question? : )

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

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36