Answer:
x= 0 , y= -8
Step-by-step explanation:
Add the 2 equations together, you would get:
9x = 0
Divide both sides by 9:
x = 0/9
x=0
Substitute the value of x in one of the equations to get the value of y, I picked the first one (5x+2y = -16)
5(0) +2y = -16
0+2y = -16
2y = -16
Divide both sides by 2:
y = -8
Answer:
So, the initial number of apples is 7.
Step-by-step explanation:
The number of apples of An, Binh, and Chi are the same. An gave away 17 apples, Chi gave away 19 apples, so now Chi's apples are 5 times higher than the total remaining apples of An and Binh. How many apples did each of you have at first? (Solve the above problem by equation or system of equations)
Let the initial numbers of apples is a.
An gave 17 apples
Chi gave 19 apples
So,
x - 19 = 5 (x - 17 + x)
x - 19 = 5 (2x - 17)
x - 19 = 10 x - 85
9 x = 66
x = 7
Answer:
<h2>90°</h2>
Step-by-step explanation:
First you must calculate the module or the magnitude of both vectors
The module of u is:
The module of v is:
Now we calculate the scalar product between both vectors
Finally we know that the scalar product of two vectors is equal to:
Where 
is the angle between the vectors u and v. Now we solve the equation for
the answer is 90°
Whenever the scalar product of two vectors is equals to zero it means that the angle between them is 90 °
1: 10x17=170
2:10x80=180
3:36 hours each day getting cars on and off 25 days so 36x25=900
4:49x34=1,666+52x3=156 the total is 1,822 dollars
