Answer:
The length of the third side of the triangle is 
Step-by-step explanation:
Let
c ----> the length of the third side of the triangle
we know that
Applying the law of cosines

we have

substitute the given values



Divide the first equation by 2 and add the result to the second equation. This will eliminate x.
... (-4x -2y)/2 + (2x +4y) = (-12)/2 +(-12)
... 3y = -18 . . . . . collect terms
... y = -6 . . . . . . . divide by 3
Substitute this into either equation to find x. Let's use the second equation, where the coefficient of x is positive.
... 2x +4(-6) = -12
... 2x = 12 . . . . . . . . add 24
... x = 6 . . . . . . . . . . divide by 2
The solution is (x, y) = (6, -6).
Answer:
Hold on i got it
Step-by-step explanation:
<u>The given expressions 7+ 7x ; 7 x + 1/7 are not equivalent or equal </u>
<u>to each other </u>
<u />
<u>Step-by-step explanation:</u>
Let us firstly assume that 7 + 7x is equivalent ( to 7(x + 1/7) so that means
7 + 7x = 7(x + 1/7)
7 + 7x = 7x + 7(1/7)
7 + 7x = 7x + 1
7x + 7 = 7x + 1
Now, subtracting 7x from both sides, we get:
7x - 7x + 7 = 7x - 7x + 1
(7 - 7)x + 7 = (7 - 7)x + 1
(0)x + 7 = (0)x + 1 thus their occurs a false statement:
7 = 1 ( we know, 7 >1)
Thus we can say that
<u>7 + 7x is NOT equivalent to 7(x + 1/7)</u>