I need help to solve plz?

Question

0.1x + 0.8y = -6.5 
0.8x - 0.3y = 8.3 

Is there one way or are there infinite way to solve

 

 

Answer 1

Given equations are 0.1x+0.8y = -6.5 ---> (1)

0.8x-0.3y = 8.3 ---> (2)

yes there is infinite ways to solve the equations.

Because we can able to multiple or divde to each side of equations with infinite numbers.

Now i can solve in elimination method.

Convert the 2 equatiions to solve simply multiple to each side by 10.

x+8y = -65 ----> (3)

8x-3y = 83 ---> (4)

Multiple to each side of equation (3) by negitive 8.

-8x-64y =520 ---> (5)

To eliminate the x variable add the equations (4)&(5).

 8x-3y  = 83

-8x-64y = 520

_____________

-67y = 603

Divide to each side by negitive 67.

-67y/-67 = 603/-67

y = -9

Substitute the y value in (3).

x-72 = -65

Add 72 to each side.

x-72+72 = -65+72

x = 7

Solution x = 7, y = -9