For this case we propose a system of equations:
x: Variable representing the amount of oranges
y: Variable that represents the amount of grapefruit
We have to meet a citrus gift package:
![60x + 80y = 780\\x + y = 12](https://tex.z-dn.net/?f=60x%20%2B%2080y%20%3D%20780%5C%5Cx%20%2B%20y%20%3D%2012)
From the second equation we have to:
![x = 12-y](https://tex.z-dn.net/?f=x%20%3D%2012-y)
We replace in the first:
![60 (12-y) + 80y = 780\\720-60y + 80y = 780\\720 + 20y = 780\\20y = 780-720\\20y = 60\\y = \frac {60} {20}\\y = 3](https://tex.z-dn.net/?f=60%20%2812-y%29%20%2B%2080y%20%3D%20780%5C%5C720-60y%20%2B%2080y%20%3D%20780%5C%5C720%20%2B%2020y%20%3D%20780%5C%5C20y%20%3D%20780-720%5C%5C20y%20%3D%2060%5C%5Cy%20%3D%20%5Cfrac%20%7B60%7D%20%7B20%7D%5C%5Cy%20%3D%203)
Thus, the package has 3 grapefruits.
On the other hand:
![x = 12-y\\x = 12-3\\x = 9](https://tex.z-dn.net/?f=x%20%3D%2012-y%5C%5Cx%20%3D%2012-3%5C%5Cx%20%3D%209)
Thus, the package has 9 oranges.
Answer:
9 oranges
Answer:
first
area of rectangle = l*b
= (3x-y+4) ( X+7)
= 3x²-xy + 4x+21x-7y+28
= 3x²-xy +25x-7y +28
Area of square = l²
= (x-2)²= x²- 4x +4
area of shaded region=( 3x²-xy +25x-7y +28) -(x²- 4x +4)
=2x²-xy +29x-7y+24
Step-by-step explanation: