+0

# how do i solve this.

0
113
2

-4x+y=4 2x+2y=13

Guest Feb 28, 2017
Sort:

#1
+18956
+5

-4x+y=4

2x+2y=13

$$\begin{array}{|lrcll|} \hline (1) & -4x+y &=& 4 \\ & y = 4+4x \\ (2) & 2x+2y &=& 13 \\ & 2x+2[4+4x]&=& 13 \\ & 2x+8+8x &=& 13 \\ & 10x+8&=& 13 \\ & 10x&=& 13 -8 \\ & 10x&=& 5 \\ & x&=& \frac{5}{10} \\ & x&=& \frac12 \\ & \mathbf{x} & \mathbf{=} & \mathbf{0.5} \\\\ & y &=& 4+4x \\ & y &=& 4+4\cdot {\frac12} \\ & y &=& 4+2 \\ & \mathbf{y} & \mathbf{=} & \mathbf{6} \\ \hline \end{array}$$

heureka  Feb 28, 2017
#2
0

-4x+y=4 (1)             -4x+y=4          (1)

2x+2y=13 (2)             4x+4y=26        (3)

We add equations 1 and 3  ,and we get :5y=30=>y=6

We replace y=6 to the equation 1: -4x+6=4=>4x=2=>x=1/2

Guest Feb 28, 2017

### 9 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details