Question

What are the solutions to the system of equations,
y=x+21
2x+y=57

Answer 1

(12,33)

Explanation:

This system can be solved using the substitution method. This is where you replace one variable by another.

Step 1:

Plug in
`x+21` for the y

Step 2:

Combine like terms

`2x+x+21=57\\3x+21=57`

Step 3:

Subtract 21 from both sides

`3x=36`

Step 4:

Divide both sides by 3

`x=12`

Step 5:

Use the first equation and plug in 12 for x

`y=12+21`

`y=33`

Step 6:

Proof of work

`2(12)+33=57\\24+33=57\\57=57`