1.) the sum of two numbers is 51 and the difference is 23. what are the numbers?

lager number:
smaller number:

2.) maya bought some books for $4 each and received a discount of $5 off of her total purchase. she spent $71 after the discount. how many books did she buy?

a. write an equation that could be used to answer the question above. first, choose the appropriate form ( +,- )with the numbers 4,5 and 71. let b represent the number of books.

b. solve the equation in part (a) to find the number of books?

What aspects of lines have to be diffrent

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.

Acentral angle measuring 160 degrees intercepts an arc in a circle whose radius is 4. what is the length of the arc the circle formed by this central angle? round the length of the arc to the nearest hundredth of a unit. a) 4.19 units b) 6.28 units c) 12.57 units d) 12.57 square units