Chapter SH, Problem 6.12EP

To determine

To solve system of equation using elimination

  $1.6x+2.2y=5.4$

  $-3.2x+4y=-2.4$

Answer to Problem 6.12EP

  $y=1$

  $x=2$

Explanation of Solution

Given information:

  $1.6x+2.2y=5.4$

  $-3.2x+4y=-2.4$

Calculation:

  $1.6x+2.2y=5.4\mathrm{........}(1)$

  $-3.2x+4y=-2.4\mathrm{........}(2)$

Multiply equation (1) by 2

  $2(1.6x+2.2y=5.4)$

So,

  $3.2x+4.4y=10.8\mathrm{......}(3)$

Then, adding equation (2) from (3) to eliminate term $-3.2x$

  $\begin{array}{l}-3.2+4y=-2.4\\ +(-3.2x+4.4y=10.8)\\ \overline{0+8.4y=8.4}\end{array}$

Then, $8.4y=8.4$

So,

  $y=1$

Substituting value of y in equation (1)

  $1.6x+2.2(1)=5.4$

On solving,

  $1.6x+2.2=5.4$

On soiving,

  $1.6x=3.2$

On solving,

  $x=2$