Answer: you bought 9 burgers and 16 tacos
Step-by-step explanation:
Let x represent the number of burgers that you bought.
Let y represent the number of tacos that you bought.
You buy a total of 25 burgers and tacos. It means that
x + y = 25
The burgers cost $3.50 each and the tacos cost $2.25 each. The total cost of the burgers and tacos that you bought is $67.50. It means that
3.5x + 2.25y = 67.5- - - - - - - - - - - - 1
Substituting x = 25 - y into 1, it becomes
3.5(25 - y) + 2.25y = 67.5
87.5 - 3.5y + 2.25y = 67.5
- 3.5y + 2.25y = 67.5 - 87.5
- 1.25y = - 20
y = - 20/ - 1.25
y = 16
x = 25 - y = 25 - 16
x = 9
Let point A (x₁, y₁) and point B (x₂, y₂)
Mid-point formula is given by:
![[ \frac{x_1+x_2}{2}, \frac{y_1+y_2}{2}]](https://tex.z-dn.net/?f=%5B%20%5Cfrac%7Bx_1%2Bx_2%7D%7B2%7D%2C%20%5Cfrac%7By_1%2By_2%7D%7B2%7D%5D%20)
The distance formula is given by:

The two formula are alike because they both need the information of two coordinate points
They are different because the mid point formula is adding up then divide by two, whereas the distance formula is subtracting then square the answer.
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Real life problem involving distance formula:
Plane A is spotted on a radar with cartesian coordinate (450, 640).
Plane B is spotted on the same radar with cartesian coordinate (350, 540)
Work out the distance between plane A and plane B.
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Real life problem involving mid point formula
Ms. Holland arranges a treasure hunt for a group of scouts. She marks two points, C and D, with cartesian coordinate (-5, 6) and (7, 10) respectively. The clue is that the treasure is buried in the middle point between C and D. Work out the coordinate where the treasure is buried.
Answer:
A: -2
Step-by-step explanation:
You want some factor k such that k(5x) +(10x) = 0. That is, 5k+10 = 0. The solution to this is k=-2, corresponding to selection A.