720 divided by 72 is 80
7 tens divided by 9 is 8
Answer:
(0,8)
Step-by-step explanation:
Answer:
x=10, y=25
Step-by-step explanation:
First, in a trapezoid, the two angles on the same leg (the legs are the opposite sides that are not parallel) add up to 180 degrees. Therefore, 4y as well as (2y+3x) are supplementary. We can write this out as
4y + (2y+3x) = 180
6y+3x = 180
Next, the angles of a triangle add up to 180 degrees. Therefore, as the angles 2y, 4y, and (5x-20) make up a triangle, they add up to 180 degrees. We can write this as
4y + 2y + (5x-20) = 180
6y + 5x -20 =180
Our two equations are thus
6y + 5x - 20 = 180
6y + 3x = 180
If we subtract 6y from both sides in each equation, we can say
5x - 20 = 180-6y
3x = 180-6y
Therefore, we can write
5x-20 = 180-5y = 3x
5x-20=3x
subtract 3x from both sides to make all x variables on the same side
2x-20 = 0
add 20 to both sides to isolate the x and its coefficient
2x = 20
divide both sides by 2 to isolate x
x = 10
Therefore,
x = 10
6y + 3x = 180
6y + 30 = 180
subtract 30 from both sides to isolate the y and its coefficient
6y = 150
y = 25
We can use a rule of three simple, direct proportion to solve this problem.
15 pounds correspond to $1.80, then the question is to find the price of one pound, the called unit rate. We state the rule of three:
15 pound ----> $1.80
1 pound -----> x
x = (1)(1.80)/15
x = 0.12
Therefore, each pound costs $0.12 that is the unit rate in pounds
$27
2.65 x 2 (since he has to go both to and from work each day) = $5.30
Add the daily cost of the water bottle (1.45) to make his total cost for one day, which is 6.75
Multiply this number by 4 (because he goes 4 days a week) to get $27 for one week.
