Multiply the first equation by -2. It turns into 4x+18y=50 and the other one stays -4x-9y=-23. Then you "eliminate" the equations by "adding" them. Set it up like this:
4x+18y=50
+
-4x-9y=-23
4x-4x= 0. 18y-9y= 9y and 50-23= 27
SO: 9y= 27 and y= 3
And then you plug that in to one equation: 4x +18(3)= 50. 4x= 50-(18*3)
4x= -4, so x=-1.
Plug it back in to check!
Hope this helps. Happy solving! :)
Answer:
It would be 80 miles in 1 hour
Step-by-step explanation:
You divide 560/7
7 goes into 56, 8 times and into 0, 0 times.
560/7=80
Answer:
( 7x + 11 )( 7x- 11 )
Step-by-step explanation:
( 7x + 11 )( 7x- 11 )
Because 7*7 is 49
-11*11= -121
7*11=77
-7*11= -77
77-77=0
so the answer is 49x^2-121
Answer: C) 
Step-by-step explanation:
First we need to calculate the area of the square base.
This is 7*7 which equals 49 cm squared.
Plug this value into the formula of a square pyramid which will be 
, now plug in the h, which is 9 cm.
Now solve.
V = 147 cubic cm.
