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6 votes
Heppp asappp plssspppppp

Heppp asappp plssspppppp-example-1
User Gosia
by
4.3k points

1 Answer

4 votes

Answer: (6, -1)

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Step-by-step explanation:

If you were to multiply both sides of the second equation by 4, then,


(1)/(2)x-5y = 8\\\\4\left((1)/(2)x-5y\right) = 4*8\\\\2x-20y = 32\\\\

The original system of equations is equivalent to this system


\begin{cases}2x+y = 11\\2x-20y = 32\end{cases}

Let's subtract straight down.

  • The x terms have the same coefficient (2) out front. This means when we subtract the x terms, they'll go away. 2x-2x = 0x = 0.
  • Subtracting the y terms gets us: y-(-20y) = y+20y = 21y
  • Subtracting the right hand sides gets us: 11-32 = -21

After those three sets of subtractions are performed, we have this new equation:
21 y = -21 and that solves to
y = -1 (divide both sides by 21).

Now use this y value to find x. You can pick any equation with x & y in it.


2x+y = 11\\\\2x+(-1) = 11\\\\2x-1 = 11\\\\2x = 11+1\\\\2x = 12\\\\x = 12/2\\\\x = 6

The solution as an ordered pair is (x,y) = (6, -1)

The two lines cross at this location.

Heppp asappp plssspppppp-example-1
User Jakob Danielsson
by
5.0k points
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