12a-7b - (4a-21b) = ...

3. A class has 11 boys and 16 girls ... How many ways can the teacher choose one boy and one girl?

How many number lines comprise the basic parts of a cartesian coordinate system?

Mikaela is competing in a race in which she both runs and rides a bicycle. She runs 5 kilometers in 0.5 hour and rides her bicycle 20 kilometers in 0.8 hour. At the rate given, how many kilometers can Mikaela run in 1 hour?

The side is in the shape of a rectangle with an area of 437 square centimeters the length of the rectangle is 19 centimeters what is the width of the rectangle

ms. edwards wants to buy pizza for her kids. she buys a salad for $20 and each pizza costs $12. if she spent a total of $80 how many pizzas did she buy

The length of a rectangle is 4 times the width. The perimeter of the rectangle is 45 inches. What is the area of the rectangle / 9960871/ce166f9f? utm_source=registration

Dominic books with 12 postcards in each book. He has 4 boxes with 20 coins in each box. If he gives 15 post cards to his friends, how many postcards and coins does he have?

Which system of equations has exactly one solution? - 2x-4y = 8 x+y=7 3x+y=-1 x-2y = -2 3x+3y=3 -Ex-by=3 3x-2y=4 -3x+2y=4

The side length of a square is shown. Which expressions are equal to the perimeter of the square? (w-2) Select all that are correct. 2 (w - 2) + 2 (w - 2) w + w + w + w - 2 - 2 - 2 - 2 4w - 2 2w - 4 4 (w - 2)

115 and 125 as a decimal