Answer:
This system has one solution (x=2 and y=2), then the answer is A.
Step-by-step explanation:
The system of equations is:
(1)
(2)
Let's multiply the first equation by 2 and subtract it to the second equation


Using this value in (1) we can find y.


Therefore, this system has one solution (x=2 and y=2), the answer is A.
I hope it helps you!
Answer:
-1
Step-by-step explanation:
Move the +16 onto the other side. We now have 52 = -52x. Divide each side by 54 to get x = -1.
Answer:
84
Step-by-step explanation:
A=bh/2.
A=(21*8)/2
A=168/2
A=84
The trick is to write appropriate equations and then solve the system of equations you've created.
"sum of two numbers is -5:" x + y = -5
"difference is -1:" x-y = -1
Add these two equations together. This will cause y to drop out, and you will be left with an equation in x alone:
2x = - 6, so x = -3. Subst. -3 for x in either equation, above, and find the corresponding y value.
Then write your solution as (-3, y ) (write in your value for y).