Well area of a triangle is

so,

The answer is 8
For this case we propose a system of equations. We have to:
x: Let the variable that represents the number of dimes
y: Let the variable that represents the number of quaters
We know that:
One dime equals 10 cents, $0.10
A quater equals 0.25 cents, $0.25
According to the statement we have:

We multiply the first equation by -0.10:

We have the following equivalent system:

We add the equations:

Approximately 3 quater coins

And two dimes
Answer:
3 quater
2 dimes
Step-by-step explanation:
the change in cost of 145-135.50 = 9.50 for an increase of students from 25 to 30. The ratio of change of cost to change of students = 9.50/5 = 1.9 and becomes the slope coefficient "m" in the formula y= mx + b. y = the total cost, mx becomes the variable cost and b becomes the fixed cost. To find b, use the data point given where the total cost = $135.50 when the students = 25, or 135.50 = 1.9*25 +b. Solving for b yields $ 88. Note that the other data point is where the total cost is $145 for students = 30. Using the new total cost equation shows that 30*1.9+88= 145