Question

solve by elimination; 0.3x - 0.2y=4, 0.4x +0.3y=5/19

Answer 1

Hi Lindy,

I would first multiply by 10 in both equations.
Then multiply the first equation by 3 and the second equation by 2.
Then cancel the y's.
you will get 17x=((120*18)+100)/19
Divide by the 17 and you will have solved for x.
leave it in a fractional form for an exact answer. Then substitute in either of the equations for x and solve for y.

I hope this helps.

Answer 2

I don't understand how to divide by19 and 17:(

Answer 3

Hi Lindy,
You will have both the 17 and 19 in the denominator.
you multiply them together and get 323. You can leave that in the denominator or divide and get a decimal answer.