What is the solution? use elimination .
4x-y=23
7x-y=21
a.(11,0)
b.(4,-7)
c.(11,44)
d.(4,7)
is it c?
4x-y=23
7x-y=21
------------subtract to eliminate y
-3x =2
x = -2/3 I suspect that you have a typo
its 7x+y= 21? sorry typo?
@damon help
4x-y=23
7x+y=21
------------so add instead to eliminate y
11 x = 44
x = 4 well that is better
7(4) + y = 21
28 + y = 21
y = -7
@damon so the answer is c?
To find the solution of the given system of equations using elimination, we need to eliminate one variable by adding or subtracting the equations. Let's eliminate the "y" variable.
First, multiply the second equation by 4 to make the coefficients of "y" the same.
4*(7x - y) = 4*21
28x - 4y = 84
Now, we have the following equations:
4x - y = 23
28x - 4y = 84
To eliminate the "y" variable, we can multiply the first equation by 4 and add it to the second equation:
4*(4x - y) + (28x - 4y) = 4*23 + 84
16x - 4y + 28x - 4y = 92 + 84
44x - 8y = 176
Simplifying the expression:
44x - 8y = 176
Now, we have a single equation with one variable. To solve for "x," we can isolate it by rearranging the equation:
44x = 8y + 176
x = (8y + 176) / 44
x = 2y + 4
Since we have an expression for "x" in terms of "y," we can substitute it back into one of the original equations. Let's use the first equation:
4x - y = 23
4(2y + 4) - y = 23
8y + 16 - y = 23
7y + 16 = 23
7y = 23 - 16
7y = 7
y = 1
Now that we have the value of "y," we can substitute it back into the expression for "x":
x = 2y + 4
x = 2(1) + 4
x = 2 + 4
x = 6
Therefore, the solution to the system of equations is (6, 1).
None of the provided options (a, b, c, or d) match the solution that we found.