Rob has 40 coins, all dimes and quarters, worth $7.60. How many dimes and how many quarters does he have?
... please solve this using if systems of equations

You are responsible for designing a new city. you are inspired by pierre charles l'enfant, who laid out the streets of our nation's capital. numbered streets run north and south, and lettered streets run east and west. avenues are named after states, and they intersect the streets on a diagonal. the streets are parallel and the intersections form similar triangles. 18th st. is 454 meters long and the intersection of 18th and k st. is 207 meters from connecticut ave. if 19th st. and k st. is 385 meters from connecticut ave., what is the length of 19th st.?

Which basic geometric term has no width, no length, and no thickness? line b. point c. angle d. plane

Clarence wants to buy a new car. he finds an ad for a car that costs 27,200 dollars. suppose his local sales tax is 7%. -how much would he have to pay? -what is the cost of the car including tax? -if clarence has 29,864 saved, can he pay cash to buy the car?