2x+5y = 10 then , 4x+4y = ?

Question

please solve this questions its need to me early for my copmtion exam.

Answer 1

Note that there are infinite solutions for 2x + 5y = 10

which is a line with slope -2/5 and y-intercept at (0, 2).

 

Thus, there is no way to determine the value of 4x + 4y.

 

2x + 5y = 10

5y = 10 - 2x

y = 2 - (2/5)x

 

4x + 4y = 4x + 4(2-(2/5)x) 

 

= 4x + 8 - (8/5)x

 

= (20/5)x - (8/5)x + 8

 

= (12/5)x + 8

 

Without something further this is pretty much all we can do.

 

I think something is missing from your problem statement.