How do you solve the following system?: 4x+5y=2,y+5=3x

2 Answers
Mar 5, 2018

x=2719 and y=1419

Explanation:

Let's isolate y in the second equation

y=3x5

Now we can solve for x in the other equation

4x+5(3x5)=2

4x+15x25=2

19x=27

x=2719

Now we solve for y

y=3x5

y=3(2719)5

y=811951×1919

y=81199519

y=1419

To check our work, let's substitute 2719 for x and 1419 for y in the first equation and solve.

4(2719)+5(1419)=2

108197019=3819

3819=2=2!

We were right!

Mar 5, 2018

x=2719,y=1419

Explanation:

4x+5y=2 Eqn (1)

y+5=3x

y=3x5 Eqn (2)

Substituting value of y term in Eqn (1) in terms of x,

4x+5(3x5)=2

4x+15x25=2

Rearranging variables on L H S, constants on R H S,

4x+15x=27

19x=27 or x=2719

Substituting value of x in Eqn (2),

y=3x5=(3(2719))5=819519=1419