Julio is making brownies for the school bake sale.
1 answer:
You might be interested in
Answer:
Cost of 1 gallon of Regular gasoline is $2.45 and Cost of 1 gallon of Premium gasoline is $2.90.
Step-by-step explanation:
Let the Cost of Regular gasoline be 'x'.
Let the Cost of Premium gasoline be 'y'.
Given:
Amount of regular gasoline bought yesterday = 2 gallons
Amount of premium gasoline bought yesterday = 3 gallons
Total Cost of yesterday = $13.60
Now we know that Total Cost of yesterday is equal to sum of Amount of regular gasoline bought yesterday multiplied by Cost of Regular gasoline and Amount of Premium gasoline bought yesterday multiplied by Cost of premium gasoline.
Framing in equation form we get;
Also Given:
Amount of regular gasoline bought today = 3 gallons
Amount of premium gasoline bought Today = 4 gallons
Total Cost of Today = $18.95
Now we know that Total Cost of Today is equal to sum of Amount of regular gasoline bought Today multiplied by Cost of Regular gasoline and Amount of Premium gasoline bought Today multiplied by Cost of premium gasoline.
Framing in equation form we get;
Now Multiplying equation 1 by 3 we get;
Now Multiplying equation 2 by 2 we get;
Subtracting equation 4 from equation 3 we get;
Substituting the value of y in equation 1 we get;
Hence Cost of 1 gallon of Regular gasoline is $2.45 and Cost of 1 gallon of Premium gasoline is $2.90.
In counterclockwise order that's
R(2,4), Q(-4,4), U(-4,3), T(2,-3), S(5,-3)
That's a trapezoid, height 7 upper base 6, lower base 9, so average base 15/2 and area 7(15)/2 = 105/2 = 52.5.
Answer: 52.5
The shoelace theorem gives the answer without thinking. We write the list on top of itself shifted and add up the cross produces:
R(2,4), Q(-4,4), U(-4,-3), T(2,-3), S(5,-3)
Q(-4,4), U(-4,-3), T(2,-3), S(5,-3), R(2,4),