Carlos thinks of a number. When he adds 17 to it, the result is 45. What is the number that Carlos thought of?

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

Solve the system of equations. y= 2x y= x^2 - 15

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?