Answer:(-3,-8),(-6,4),(1,-1)
Step-by-step explanation:
Given
Vertices of the triangle are

Coordinates (a,b) when reflected about x-axis is given as (a,-b) i.e. Y coordinate changes its sign

Answer:
No, Angela is not correct.
As the method Jim was performing will also lead to the solution.
Step-by-step explanation:
We are given first equation as:
Ax + By = C
Second equation is:
Dx + Ey = F
Jim solved the equation as:
He begins by multiplying equation (1) by D and equation (2) by A.
and so by subtracting both the equations he will obtain a value of y.
and then put the y-value in any of the given two equations to obtain the value of x.
Angela Method:
you should have multiplied equation (1) by E and equation (2) by B.
and when she will subtract both the equations she will get the value of x first and then when she will put the value of x in any of the given equation she will obtain the value of y.
But both will get a value for x and y.
Hence, the method Jim was performing was also correct.
Answer:
Plane's speed is 150 miles/hour
Step-by-step explanation:
Let the plane's airspeed be x
Speed of wind is 30 miles/hour
When a plane flew with the wind , Speed = (x+30)
So, the speed plain with wind on going = (x+30)
Since we are given that on returning plane fly against the wind .
So,When a plane flew against the wind , Speed = (x-30)
So, the speed plain against wind on returning = (x-30)
Distance = 720 miles .

So, time on going 
Time on returning 
Now we are given that the total time for the whole trip (going + returning) = 10 hours.
So, 



![1440x=10(x^2 -[30]^2)](https://tex.z-dn.net/?f=1440x%3D10%28x%5E2%20-%5B30%5D%5E2%29)






So, the plane's speed is 150 miles/hour
This question is incomplete because there is a missing variable. You would need the width or length for me to complete this.