Answer:
B.
Step-by-step explanation:
21 X 2 = 42
42-7 = 35
35 + 21 = 56
Answer:
{x,y,z} = {-18,4,2}
Step-by-step explanation:
Solve equation [2] for the variable x
x = -10y + 2z + 18
Plug this in for variable x in equation [1]
(-10y+2z+18) + 9y + z = 20
- y + 3z = 2
Plug this in for variable x in equation [3]
3•(-10y+2z+18) + 27y + 2z = 58
- 3y + 8z = 4
Solve equation [1] for the variable y
y = 3z - 2
Plug this in for variable y in equation [3]
- 3•(3z-2) + 8z = 4
- z = -2
Solve equation [3] for the variable z
z = 2
By now we know this much :
x = -10y+2z+18
y = 3z-2
z = 2
Use the z value to solve for y
y = 3(2)-2 = 4
Use the y and z values to solve for x
x = -10(4)+2(2)+18 = -18
Answer:
Graph (C)
Step-by-step explanation:
To find whether the graph\table represents a relationship or a function we have to analyze the input-output values given.
Graph A.
In this graph for every input value (x-value) there are two output values (y-values).
For x = -2, y = -2, 2
So the graph doesn't represent a function.
Graph B.
For every x value there are two y-values
For x = -5, y = -3, 3
So the graph doesn't represent a function.
Graph C.
For every input value there is a different y-value.
Therefore, graph represents a function.
Graph D.
In this graph for x = 3, y = 1, 2, 3, 4
For one value of x, there are four values of y.
Therefore, graph doesn't show the relationship.
You should definitely improve the quality of the image, because I can't see anything clearly.
Also, the 4th answer is hidden.
Hi there!
To solve this problem using substitution, we need to set x equal to a value and substitute it into the other equation.
Since
x - 4y = 5,
x = 5 + 4y
3x - 7y = 10
3(5 + 4y) - 7y = 10
15 + 12y - 7y = 10
15 + 5y = 10
5y = -5
y = -1
Now that we know y is -1, we can substitute it back into the equation to find x:
y = -1
x - 4y = 5
x - 4(-1) = 5
x - (-4) = 5
x + 4 = 5
x = 1
So, your answers are x = 1 and y = -1.
Hope this helps!
