Answer:
B (5, 13)
Step-by-step explanation:
9x + 4y = 97
9x + 6y = 123
To solve by elimination, we want to <em>eliminate</em> a variable. To do this, we must make one variable cancel out.
First, we can see that both equations have 9x. To cancel out x, we must make <em>one</em> of the 9x's <em>negative</em>. To do this, multiply <em>each term</em> in the equation by -1.
-1(9x + 6y = 123)
-9x - 6y = -123
This is one of your equations. Set it up with your other given equation.
9x + 4y = 97
-9x - 6y = -123
Imagine this is one equation. Since every term is negative, you will be subtracting each term.
9x + 4y = 97
-9x - 6y = -123
___________
0x -2y = -26
-2y = -26
To isolate y further, divide both sides by -2.
y = 13
Now, to find x, plug y back into one of the original equations.
9x + 4(13) = 97
Multiply.
9x + 52 = 97
Subtract.
9x = 45
Divide.
x = 5
Check your answer by plugging both variables into the equation you have not used yet.
-9(5) - 6(13) = -123
-45 - 78 = -123
-123 = -123
Your answer is correct!
(5, 13)
Hope this helps!
Answer:
A is the cheapest deal.
Step-by-step explanation:
find unit rate; cost / quantity
20.20 / 10 = $2.02 per gallon
26.04 / 12 = $2.17 per gallon
28.24 / 24 = $2.01 per gallon
30.45 / 25 = $2.03 per gallon
Answer: the correct answer is A
Step-by-step explanation:
I just took the test
Answer:
Step-by-step explanation:
The surface area of a rectangular prism has six sides so you must find the sum of the areas of all sides.
A=2xy+2xz+2yz
A=2(xy+xz+yz) you have x,y,z as 3,2,4 so
A=2(3(2)+3(4)+2(4))
A=2(6+12+8)
A=2(26)
A=52 cm^2
So the problem is asking you to combine equations, in this case the Y factor will cancel out so you will be left with the X factor and the total after you add both of the totals together,
6x-4y=16
5x+4y=6
6x-5x=x
16+6=22
x=22
